It works for me.. But I run two amps in stereo (one panned hard left, the other hard right) and also output my signal to a bass amp(with an octave, EQ etc.. ) I can't play one amp at a time anymore, it always sounds thin and feels like something is missing. The downside is the blended tone is really only best appreciated when standing in between both cabinets. I was doing it with my Mesa tube amps as well, and realized I didn't want to bring three heavy (and expensive) amps if I play out. Hence why I picked up the Axe FX. And it's also why I could really use the third amp/cab block.It was a bit of a surprise for me the first time I ran multiple amps at once years ago. Two amps didn't sound twice as good as one amp.
It didn't even really sound 'better', mostly just maybe more versatile. So not being rich I stuck with one amp.
Are any people finding two amps at once the magic sauce for their tone?