Feature:
So.. I actually have the YPG525.. which is virtually the same thing.. so.. The survival kit is extremely useful. Sustain pedal = rad. There's also a cloth to place over your keys when you're not face-melting (and when you are face-melting, it can be used a cape..(yes, like a super hero)). Pitch Bender with adjustable range for all you techno freaks out there. I would suggest buying a USB Flash Drive for it if you intend to record on the User Song feature. Though each song has 5 tracks (and an accompaniment track which is virtually useless because the styles and easy song arranger sound so generic), With only 5 songs, space fills up quickly for the creative soul. The Effect Banks can be invaluable if you are playing a song with multiple instruments involved. Built-in metronome (of course). The only thing I really wish that it could do would be to change time signatures in a recording without having to go to another track. The hammerlock keys provide a good transition for anyone preparing to move from the traditional button-push keyboard to the full on Grand Piano.

Quality:
It looks very state of the art. Dust doesn't even gather well on it. It's quite a large board with 88 keys and due to that, I have banged it on walls and door frames lugging it around, but it just keeps on trucking. I wouldn't be surprised if I dropped it and it still worked.

Value:
I'll say that it's definitely worth the buy.

Desirability:
It does look pretty awesome. In a dark room with just the blue screen lit up. pretty inspirational. I also like the clicking wheel on the right... I don't know why. I just do.

Sound:
The Live! Grand Piano is about as realistic a sound as you can get. The panel sustain and the sustain pedal are two distinct, yet practical effects. Though there are nearly Five hundred other great voices, personally I am in love with the Sweet! Soprano saxophone.. Looks like Kenny G is out of a job. It has instruments that I had never heard of, never thought existed, and never thought that anyone would actually be able to play. Awesome.

Ease of Use:
I've had two keyboards before this one, and I must admit that this is definitely the best yet. Although I knew the basic principles of User Song recording before, I'm sure with a little time in the manual, one could easily learn how to successfully use the instrument. I still haven't been able to download music from the net due to the fact that you have to pay for it (of course).

Support:
I had no need for support, but Yamaha sent a DVD detailing all of the aspects of the keyboard anyway! How's that for support?

Overall:
I've been quite thoroughly satisfied with this board. I would be pretty much lost without it. If you've been playing for a while and are looking to step up your game a bit, but you don't have the type of budget that allows you to buy a $1500 keyboard, then this is definitely for you. Intermediate players are probably best fit for this board, though anyone can use it. Wish it had more tracks, and the styles sound kind of outdated (which is to be expected when trying to define a genre in one pattern), but it makes up for those with the number of instruments, sound quality, and sheer beauty.