I played the small box at Musikmesse and own a BE100.
I would say Channel 1 on the SB is more like another version of Channel 2. So it's a seemless progression: clean to crunch in Ch1, crunch to lead in Ch2, and very similar and together sounding. The clean and BE/HBE on the BE100 however are very different sounding channels and there is no dirt to be had in the clean channel. I found the dirt channel on the SB a little less in the low end (which is good IMO).