The original KO got skunked 5 ears ago in a comparison test by practically all of its competitors (
see here). The KO2 shares the same tread as the KO, but a different (improved) compound, which nets 10-20% improvement on all fronts, according to BFG.
Of course tires are a subjective thing. You look up any tire and there will people who love it and people who hate it. Generally, for most tires, it is a 60/40 spread - KO2 no exception.
I've two friends who've run the majority of A/Ts on their rigs, and both of them rate the KO2s among the worst of the A/Ts. One really likes the Wildpeak AT3 (which by all accounts is a great tire), the other loves the Cooper ST Maxx, which will be my next tire.
The KO2 is rated as a 50/50 tire, which makes it a bit of a loner in that regard, but it seems the 60/40 and 70/30 tires are just as good offroad, while being better on road. So for a better street tire, look at the Cooper AT3, the Wildpeak AT3W, or maybe even the Firestone Destination AT (tho I expect durability on that one to not to be as good). The Duractrac is the undisputed king of snow and ice, so if you deal with those regularly, it is pretty much a no brainer. I'm also told Nokkian makes some tough, quality tires.
Slightly more aggressive than the KO2 is the hybrids (cross between A/T and M/T), of which there are three: the Cooper ST Maxx, the Toyo RT, and Nitto Ridge Grappler. Nitto and Toyo are sister companies, and are much loved by Raptor owners, but they are really heavy (7-12lbs heavier per tire). Because they are more aggressive, they are louder, but from what I've gathered they can actually be quieter than the K02s. I've found my BFGs always get loud after 10k - I'm expecting most of these other options to be quieter than my K02s are now.
The stock tires hold the advantage of lightest weight* and highest speed rating.
*It seems an E rated K02 is actually lighter somehow - not sure if that's a typo or not, but certainly interesting if true.