I was not impressed when I first plugged this compressor in; the Sustain knob was adding tonnes of gain, and the level knob seemed to not be doing anything. After playing around with it a little more, however, I've given it the benefit of the doubt and assumed something went wrong loading the toneprint onto this particular model.
And that, right there, is what makes this pedal so great; TonePrint. Whatever compressor you feel you need, you'll find a TonePrint that takes you there. If not, you can make one yourself! Don't let its Digital-ness scare you away, it's an improvement, not a curse. Thanks to the incredible amount of versatility offered by the TonePrint, you can get anything you want out of the Hypergravity mini (and as I understand it, any TonePrints made for the standard size model are compatible here, the only difference is the lack of a blend knob on the mini). Personally, I've been using the Transcomp, a TonePrint designed by John Petrucci (yes, THAT John Petrucci) to be as transparent as possible. While I wouldn't call it wholly transparent, it's the sound I want; the attack knob lets it give your cleans a Dyna-Comp-y pop, or you can round the attack off entirely and just as some lush sustain to your dirtier tones.
I will say that the initial attack of the note can feel a little harsh, but it is highly likely a little tweaking of the TonePrint would resolve that (it might even just be the way it's reacting to the rest of my signal). This is a minor issue though; I've gotten plenty of good stuff out of this Compressor. Highly recommend; simple enough to a people to a relatively inexperienced Compressor user, but with enough options to satisfy the most ardent of aficionados.
