Regarding the power amp question, they both sound nice. (So long as you don't get one of the very early 50:50's, they were voiced for the studio preamp and need a deep extend mod to sound good with the triaxis). I actually like the 50:50 better, it sounds fine and it's quite a bit lighter. There are some differences but at low volumes there won't be much difference. The 2:90 is a little different and some people like the feel of the simulclass thing, but to my ear and hands the volume required to feel the difference is just beyond what you can get away with in most club situations. The size place you need to be playing in to get either one to break a sweat almost doesn't exist nowadays! I've played big outdoor stages and never had to turn the 50:50 up past 3 or 4 on each channel. And the low power options on each amp I find not terribly useful because you will kill people if you turn them up loud enough (even in low power mode) to get power tube distortion. Of course, the beauty of the triaxis is that you can get great tones without relying on your power tubes for breakup, so you can have a consistent sound at any volume. :mrgreen: