Wow very good, informative thread. Thanks.
Now I'm thinking the Fx8 may be more for me. I don't foresee doing the FRFR thing. Nothing wrong with FRFR, but a lot of times I play through provided amps. Sometimes bringing our own amps is very much discouraged. And the provided back line is surely not going to include FRFRs. So I design my sounds to go into a clean amp, whether it be my own Quilter amp or some Fender Hotrod or Marshall half stack I get.
Well I guess I could do the Ax8 straight into the PA. But then I'm at the mercy of the house monitors. I don't know. I'm sure it would sound great FOH but I might get a less than inspiring sound on stage that may cause ignorant band mates to look at me like, your rig sucks.
Amp modeling is convenient feature. But since I'm really interested in clean amp sounds (not so much the Rectifier high gain stuff), I can do that very well with a SansSmp in s pinch. My current analog pedalboard sounds great going direct through an old SansAmp.
Anyway I'm rambling. But interesting food for thought in this thread.