I'll chime as I've owned mine for a little over a year now. I pretty much agree with the above description. The crunch channel has a nice JCM 800 voicing with a lot more gain. It's not totally a Marshall crunch but similar ballpark. The lead channel which can be on both master volumes is a mix between an SLO and Mark series boogie. If you run the channels like I do you can make it a two channel amp with a solo boost. The footswitch will allow you to get three different volumes while the front two masters can have different gain and voicing selections.
The switches on the front are subtle but definitely noticeable. There isn't a setting or switch position that sounds bad. I've never had an amp that could essentially sound great no mater how it was EQ'ed.
I run it with celestion blackbacks in an old Marshall cab and a KSR cab with H30's. In addition, I have tried 6l6's and EL34's, and both sound great.