Don't get me wrong, it has quite some gain on tap and I've used it as a high(er) gain overdrive in the past. But the low gain area is where it really shines.
With a 3 band eq, volume, gain, 2 channels, a -8dB pad switch and a switch that turns the "Active" footswitch from bypass to mute, it actually has many more features than you'll usually find on drives. This probably stems from the fact that EBS also advertises the ValveDrive as a tube preamp, not just as a tube overdrive.
The EQ section takes a little getting used to - but it is very well explained in the manual, so don't worry. The pedal is also huge and heavy as hell, and that's where the 4 stars for handling come from. The sound, however, is well worth the effort.
As for sound, the 2 channels are very different in nature. The modern channel, indicated by a red LED above the "Vintage" footswitch, produces a very focused, punchy sound that retains clarity even on higher gain settings. Upon pressing the "Vintage" switch, the LED turns to a warm yellow - welcome to the vintage channel. This one produces a much more "overdriven tube amp"-like sound: dirtier, grittier, crunchy and a lot less focused/punchy. Unfortunately, it loses volume (or at least perceived volume) on higher gain settings when compared to the modern channel. On low gain settings (im running the gain at about 9 o'clock) they're very well balanced, however, and you can really use both channels as independent sounds. Also, I've never heard a pedal do low gain on bass better than the ValveDrive.
The quality is great as always, built like a tank, just the right amount of resistance when turning the pots and quality switches. It also looks cool as hell with the chrome tube cage and the orange lighting inside it.