A couple of caveats before I say anything further:
I have never been an OD pedal kinda guy. I've always relied on the amp's gain. Played Mesa all my life and just love them without anything in front. I've tried pedals but always end up going back to the basic amp.
I don't have an extensive collection of OD pedals to compare.
I've seen a lot of comments about the OD stomps in the Kemper being nothing special and not as good as sticking a real OD pedal in front of the KPA. I decided it was time I tried out properly myself. Last night I tried my Boss DS1 both in front of the KPA and in a loop. I A/B tested the real pedal against the DS1 stomp in the KPA. I started by playing live then recorded a loop to let me tweak easier. Try as I might I just couldn't get the Kemper DS 1to sound exactly like the real Boss pedal. This was actually a good thing though. The Kemper DS1 sounded much better to my ears. The Boss always had a bit of mud in the bass or low mids that the Kemper didn't suffer from. They were fairly close and I think I would have recognised them as the same style pedal in a blind test but would have assumed they were just set up slightly differently.
Anyway after about an hour playing with it I unplugged the DS1 and stuck it back on the shelf. Maybe I'll try my Full Drive 2 at some point if I can ever be bothered dragging my old pedal board out but I don't see that happening anytime soon
For me the Kemper ODs are as good or better than the DS1 and certainly good enough for me if I ever want to stick a pedal in front of a profile. Mind you, I would still be interested to try any new OD stomps or OD updates that might come along in the future