I've owned the digiZoid ZO for just a little while now, but it has really grown on me! It's the perfect amp for bassheads. It's pretty much an external EQ for your music player. It was absolutely fantastic using this listening to dubstep. The build quality isn't the best, mainly a bunch of cheap plastic but it's fairly lightweight so I'm comfortable throwing it around. It's really straight-forward as it only has one button which is used to increase/decrease the bass and power on/off. I'm not a huge fan of the colours as a measurement because it's not as easy to maneuver, "What's your favorite setting?" "Oh, I really like kinda orange-red". Also YOU CAN'T USE LODs. There is no volume control on this amp so you can't use an LOD for an iPod or anything with it. There is a fairly present hiss when there is no music playing, but you can't really hear it once the music starts. That SmartVektor voodoo-believe it or not- WORKS. Yeah, that's right, it works. It gives your music a more full sound, I've also noticed it cleans up a bit of the distortion.
Overall, perfect for bassheads, good if you can find it for a cheaper price, makes your music sound better. I think it's a good buy!