I love my Hyperdrive. It is very versatile, has some great sounds. With the frequency and drive knob it's easy to go from some subtle grind to Sabbath-esque fuzz to full out distortion, and the mix knob is great, keeps the original signal better than most I've tried. Plays nice with active basses too.
Only thing I dislike is the size, it can be a bit limiting real estate wise. I knew it was big when I ordered it, but to be honest, I was pleasantly surprised to see it wasn't as big as I thought it would be.
Quality is alright, but it isn't as heavy as its size would indicate. That's not a bad thing of course, but it does make it feel a little "cheap".
The knobs are recessed, so no accidental tweaking, but the "Q" and "+10" switches are a bit hard to reach if you have big fingers.
All in all, it makes my dinky practice amp shine, and my 4x10 breathe fire. And if you run a seperate EQ afterwards... Sploosh.