Feature:
for being so small, It does have an Auxillary input. I plugged in my ipod and played some Metallica Master of Puppets to compare sound. and I was Impressed. A Nice feature for jamming along to your favorite tunes. the 3 knobs for gain,tone,volume allow some nice flexibility and shaping.

Quality:
It is lightweight and plastic so it does not fall out of your guitar input. knobs are plastic but if you take care of your stuff you should be fine.

Value:
for the price, its well worth it for what it does. Great for jamming late night and or going on vacation and keeping up on your licks.

Desirability:
looks cool, sounds cool, is cool.

Sound:
On Point with metal sound. Can throw some serious Pinch Harmonics on this headphone amp. has 3 knob controls: Gain, Tone, Volume. By Putting the Gain to 1 or 2 you can get some decent clean out the headphone amp. putting it on 10 is some serious metallica,Killswitch Engage sounds.

Ease of Use:
plug it in and jam. Simple

Support:
no experience.

Overall:
I tested this on my esp EC-1000, and my fender strat. I like how the device fits in either guitar, The device fits awesome in a strat guitar giving you easy access while jaming to change the tone and gain on the fly.

Feature:
Gain, Tone, Volume. You really don't need anything else.

Quality:
Don't leave it in your guitar. One slip will break the 1/4" plug.

Value:
I've been playing guitar for years. This is the BEST $40.00 I have EVER spent on guitar gear.

Desirability:
Looks aren't as important as tone.

Sound:
Massive gain half stack sound in a credit card size package.

Ease of Use:
Set the dials, plug in your headphones. Rock 'till you drop and no one has to turn up the tv.

Support:
Not needed yet.

Overall:
This is the hig gain sound for the headphone amps. Take an 1/8" cable, plug it into your computer mic, record like your jamming a Mesa.