Feature:
Many have mentioned the s90's lack of a built in sequencer or sampler. I actually do not mind the absence of such features. Mine came with pre-packaged sequencing software which is more than sufficient for recording needs, and smapling is what samplers such as a Korg Kaoss Pad are for. The arpeggiator is absolutetly wonderful as well, and the effects options allow for complete customization of a voice. Not only this, but you also have the option to transfer MIDI data to a computer via USB 2.0 (using a printer cable), which is incredible handy. The sixteen track recording mixer and the four track "Performance" mode is the icing on the cake, giving the s90 great versatility. Also look to the three expansion slots.

Quality:
I am very "hard" on my possessions, and have the "touch of a blacksmith" according to many of my close friends. Yet all the same, the s90 has not yet broken, faltered, or even stalled or frozen in one year of use (which cannot be said for my laptop). There is little to worry about braking, as the build is solid.

Value:
The Yamaha s90 is all about balance, a balance between performance and production, and balance between value and features. If you're looking for a keyboard/studio of great quality but are on a budget, then look no further than the s90. For a thousand dollars less than a Motif 8, you get the most beautiful piano voice in the world, and you still get the same Yamaha quality.

Desirability:
The the sleek, black color and the simplisic layout of buttons and sliders make the s90 a sort of "stealthy sexy" appearnce one might associate with a ninja. But don't be disarmed by its simplistic appearnce. Beneath that stealthy exterior lies a analog and digital killing machine. It's big, but not clunky or unweildy as many 88 key synths are. The smooth weighted action only helps it seduce you into it's world of endless pleasure. Once you play this synth, it will become an unbreakable addiction as it has for me.

Sound:
The piano, as many have stated before, is wonderful. I also happen to be in the possesion of a Boston grand piano, and I can say that the s90's actually sounds far better. "Steinway perfect" if you will. That is not the only good part about its sound quality however. The leads are crystal clear and, well, so is everything else. The accoustic voices, (such as the violins and flutes)are incredibly realistic, so much so, that it feels as if you have not a keyboard, but an orchestra at your command. As long as you have a good set of speakers or some decent headphones, this is the keyboard for you. As an example, my friend owns a trombone and came over to see it. We compared the two's sounds and the s90's was actually better!

Ease of Use:
When I recieved the s90 for Christmas from mum and pap, I had never touched an electronic keyboard before in my life. Within an hour, I was editing voices, changing Performance Mode rhythms, and generally having a blast. As always, it pays to read the manual, and if you seek to use the computer recording software, it may take a day or two to get down the basics.

Support:
When I was starting to mess with the sequencing software, I called on Yamaha twice for help (not for technical issues, just for some general advice). They were not only expedient, but patient, friendly, and even offered humor at times. Expect your probelms to be solved with speed and effecience beyond your highest expectations.

Overall:
Chances are that the s90 will stay with me for the rest of my life. I'm already saving up to get three plug-in cards for it, and play on it at least once a day. I believe that the Yamaha has given me the perfect audio weapon, something I will never replace or sell, for any price. If you're still bent on having a dedicated workstation such as the Motif 8, a Korg Triton or Triton Extreme will sate your tastes, and completment the s90 well. I have already made an album off of the s90, and am working on another.

Feature:
Lacks sequencing/sampling, but that's not what this board is intended for. Good selection of voices, editing, effects. Limited on board storage memory for performances and backups. No problem using an external USB drive to correct for this. Would have liked to have seen a firewire interface, and colour display for the ES version.

Quality:
I'm always confident when I purchase Yamaha products, and they have never let me down. They obviously take quality very seriously, and it shows. Fit, finish, quality of material are all first rate.

Value:
The price is excellent, considering what you get compared to other boards. The sound quality/quantity are excellent compared to an RD700 in the same price range. Add $$$ for a Motif or Fantom to get the sequencing that you would probably do with a computer anyways.

Desirability:
Nice, solid, functional piece of gear. I don't know about the sex appeal, I wanted it enough to buy it, how's that.

Sound:
The best piano sound out there right now. Drums are pretty good, the remainder are fine for filling in as pads. Connected to a pair of half decent monitors (BX8a's), it sounds quite impressive.

Ease of Use:
I have to give a less than perfect score for this. I play piano, first venture into synth boards. The manual could have been written to be a bit easier to understand. For someone with zero experience, I recommend getting the instructional DVD for first time use.

Support:
Yamaha support is always excellent.

Overall:
An excellent keyboard, period. Doubt I'll replace this for a long time. There is a learning curve to get the sound you want, but easy enough to sit and play right away. Add some decent monitors, and a software sequencer, you have a pretty good home studio. I'll probably sell my Yamaha U3 upright now that I have this.

Feature:
The only reason I did'nt give it a ten is because it lacks recording. All the other features are great.

Quality:
The quality of preety much all Yamaha products is amazing, including this one. Yamaha is known for great quality.

Value:
I think this is the best keyboard out there you can get for this much money.

Desirability:
It looks great, its fun to play, If mine ever broke I would hang it on my wall just to look at it.

Sound:
The sound is amazing. The first time I went in the and tried it out I knew it was what I wanted because the sounds are as good as the Motif.

Ease of Use:
If your just getting this for a piano voice or just playing around with it, its easy to use. However, if you try to edit voices or change the locations of a voices it gets really confusing

Support:
I hade a problem with my Keyboard and brought it in to "The Good Guys". They were like the only repair peole any where near me and it was a preety long drive.We had to keep nagging them to finish up on my keyboard. Even though it took a long time, they did repair it well.

Overall:
I expect to have this keyboard for a very long time.

Feature:
One thing that astounds me is the arpeggio feature that turns every synth/voice into its own set of unique tracks.

Quality:
All I can say is...its Yamaha. Growing up with various Yamaha grand pianos and guitars I know what to expect and this keyboard deserves nothing less than a 10.

Value:
For the amount of features and astounding quality of sound and functionality this keyboard is a steal.

Desirability:
This keyboard just looks incredibly sexy. The maroon-colored end caps and accents flow with the black finish of the casing. One thing that could be cooler would be a higher-resolution display but the included one in no way needs improvement.

Sound:
What better a name than Yamaha to produce the most incredible sounding piano? Powered by M-Audio BX8a Studio Monitors this keyboard outputs incredible sound on every level.

Ease of Use:
To pick up and play is very simple, though creating your own programs and customizing it to your own style can be challenging at first, though the extensive included documentation solves this.

Support:
Never had to deal with Yamaha for support...their stuff works and works flawlessly

Overall:
I will never need a new keyboard.

Quality:
So solid, I've never had a problem with it andI do alot of traveling with it!

Sound:
I've never hear a more crisp sound in my love come from something digital! It's so easy to function and you will not be dissapointed with what you pay for!

Overall:
Best Buy I could make!!! Its an amazing peice of equipment to have. You know you've got a good keyboard when it can stand next to a rhodes and a grad and produce VERY similar tones.

Feature:
Favorites option is helpful for navigating through thousands of patches to find the one you want.

Quality:
Seems pretty well built. Althoug I wish volume sliders were recessed. They are exposed and subject to getting hit or bent (which I did) when moving keyboard around. When you carry this keyboard its so long you feel like you should strap a red flag on the trailing end.

Value:
Great piano and action

Desirability:
Black is the right color since silver is so hard to keep clean.

Sound:
The keyboard cuts through on stage nicely and the wieghted keyboard is not to stiff. You do not get finger cramps and broken fingernails from playing a 4 houg gig. Piano sounds are the main selling point since I am primarily a piano player. Pinao sounds are rich and extremely dynamic from very soft playing to loud.

Support:
No

Overall:
Korg, Roland and Yamaha are all great keyboard companies. They each have their strengths and weaknesses in sounds. I've owned them all. I just liked the piano on this S90 ES so much I had to get it.

Quality:
The black finish is harder to keep clean than my Motif. No biggie. I like the slider controls better on my older Motif 8. I agree with the person about recessing them. Overall, the quality is typical Yamaha. Excellent and should Not be a deciding factor for purchase.

Value:
I would pay $500 more for this Synth... just for the sound alone.

Desirability:
You want it! Your neighbor wants it! Why can't they make the Motif available in this color? I have to keep a drewl towel handy when I am around this thing.

Sound:
OK, yes, the Piano is extraordinary! What about the rest of it? All I will say is

Sound:
The "Intimate" piano patch is really very nice. "Natural" cuts through a mix like hot knife through butter. Dynamically more expressive than RD-700sx with a more "sophisticated" tone.