Just got it yesterday, the one without the poweramp, as I figured I would have a lot of flexibility in amping it if I need to. I don't gig, I only play at home quietly. My signal chain is:
guitar > KPA > Alesis iO2 Express interface plugged into Mac Mini > KRK Rokit 5 Studio monitors
So, I downloaded all the updates, and all the extra rigs, and about 100 or so new rigs from the Rig Exchange. I will say, I am impressed. Nothing I've done prior to this (after LOTs of searching and trying different plugins, preamps, etc.) sounds this good. So many profiles sound super good. Now, through 5" studio monitors, the sound is not big - I would need bigger speakers for that. I'm tempted to buy a large powered monitor just to have something like that on hand. Also to test the KPA further (I bought it from Musiciansfriend, where there's a 45-day return policy). But I like what I'm hearing so far.
BTW, I got the white one - at age 44 my eyesight is not the best for reading the labels for all these buttons, and the black one looked like it would be a nightmare in that regard. The one is much easier to read the labels.
I like the tuner on the KPA, also.
So far, so good.