I always get sucked into these discussions when I see em.

Personally, I didn't and still don't like 99% of the profiles that are out there, free or paid. That's why I started making my own and then selling them. If you mic up your amp, and make a profile with the Kemper - it's going to sound like that miked amp. Period. I had a friend over with a really cool GT Soul-O amp. We hooked it up to a cab in the next room, miked it up through my monitors, made sure we both liked how it sounded, then made a profile of it. I didn't let him see which was active - the Kemper profile or his 'real' amp. He couldn't figure out which was which, by sound OR feel, and he even rolled his guitar volume down to try to figure it out. I've done this with a couple other friends.
...and btw, comparing a kemper profile of an amp to your real amp is going to be a little wonky at times because I have several JMP marshalls and I can tell them apart by tone and sound, they are all different. Same for tube amps, I've heard some that were a little close but no two were exactly alike. Add to that different brands of tubes, speaker cabs, microphones, mic placement and yeah, you've got a world of variation with the same model amp.
I'd advise the OP if he can keep tube rigs and get the Kemper, do it! Best of both worlds, and you can profile your tube amps and if you get good profiles, may want to sell those tube amps! Or keep them around, nothing wrong with that either. Had a guy ask on another board why I was selling 'all my tube amps' - I'm not, still keeping over a dozen. I love amps, but the Kemper is really awesome and I love it. Playing a gig tonight, taking all my amps with me - in the Kemper. Can't beat that.