Just thought that I would chime in with my recent experience taking the Kemper out for its first gig.
Beforehand, I did have the advantage of having run an axe fx 2 rig for around a year. I experimented with both FRFR monitors and power amp/cab setups there so I was familiar with the different setups.
When I bought the Kemper, all of the different options came flooding back. How the FRFR sounded great, but the "real cab" tone was lovely to have on stage too and to be honest, I was completely overthinking it. It was a real issue with the axe fx to find the right setup and get everything sounding good on stage but the Kemper was just sounding great no matter what it went through. In the end, I just went with the lightest and easiest to set up option, single 1x12 and straight into the PA.
Sounded awesome all night!