Got it!
Build: Excellent, sturdy, everthing feels smooth and high quality.
Clean channel: Sounds pretty much exactly like a twin reverb which is good, the eq is very inter-dependant but the bright and shift buttons really make the sound jump out at you. It can be slightly overdriven and sounds more amp like than most pre's.
Rythm channel: Sounds right in between a marshall and a mark series boogie. Again, the tone switches really tweek the mids and highs. With the gain way down I could get a nice vintage ampeg v4 overdrive and cranked up is more like cliff burton territory. It has a tubey compressed, sound.
Lead Channel: Same as the rythm but with more gain, maybe alittle more compressed.
Cab simulation: These actually work very well. The open back 2x12 sim sounds smaller and with less low end and the 4x12 closed sim has a bigger buttom end with some low-mid punch. I prefered the 4x12 but for guitar instead of bass, I can see where either would be good.
I tried it as a stand alone pre and in my effects loop for distortion. It sounds good either way to me. A bassist could definitely use it for his main preamp with no problem. There seems to be no low end loss in the clean channel at all. I will most likely use this with my guitar mostly since I actually prefer solid state distortion for bass but, it's a really nice sounding pre. They are very hard to find and I think that you actually have to custom order them now. Kinda pricey as well.