There's a real simple thing that people forget when they rip on Kemper clips - whatever you feed into the kemper with a microphone for profiling, is what you're going to get back. If you used a crappy mic or bad placement or a bad cab or whatever and did a profile, it's what you get. The best way to profile amps, and I didn't really do this until I had the thing several months, is to have the Kemper itself hooked up to studio monitors for output in another room isolated from your recorded amp so you don't hear the original at all. During the profiling, you can A/B check the kemper sound against the sound of the amplifier miked up - to verify the tone before you save it.
Simple experiment I tried one night at band practice - other guitarist played through my Bogner 101B into one of my '72 marshall cabs. I played through the kemper, solid state power amp (rocktron velocity) into my other '72 cab using a profile I pulled of the bogner + 72 cab. Of course, I turned off cab emulation since I was going into a real cab, but it was REALLY close, especially since he and I obviously play a little differently and were using different guitars/pickups.
I still have 99% of my real amps (I sold my Mesa Maverick after profiling the crap out of it) but once you get used to using the kemper, it's just so much nicer having your tweaked amp tone out there to FOH. I will be the first person to admit nothing sounds as good as a cranked halfstack, but in over 20 years of gigging I can probably count on my hands the number of times I had a good sound out front.