I have owned them in 35's and 37's. The 35's were quiet but I rotated them every 3000 miles. That set had about 48,000 miles and would have probably gone another 15,000 easy. I had bought those new and wheeled callalantee, flats, the farm, harlan,ure. Never punctured a tire when I had 35's. I sold them and bought a used set of 37 km's. They made noise on the road and I punctured a sidewall in Sparta Tn. at Golden Mountain orv. A buddy of mine punctured a brand new 44 swamper the same day so I figure it was just some sharp rock and the fact that it was raining and we were hammer down everywhere we went. I busted another one after our harlan trip this year when I sheared a caliper bolt driving the caliper into the wheel. Busted the wheel and flatened the tire while going 70 mph on hwy 16. That blew the sidewall out in 4 or 5 different places. I would put that down to me not checking my junk after wheeling. Those tires took me everywhere in Harlan. Lower damnation, Little Jager, Rail bed, Mason jar, etc. etc.
If you are looking for a good all around tire, It is hard to beat. They are not as good as a swamper in the mud or as good as a krawler or trep on the rocks. But a damn good compromise for a street tire. Having run the km1, I would have to say that the km2 beats it in almost every aspect except certain types of mud. In thick almost dry mud, the km1 seems to clean out better than the km2. As long as you rotate them, you should get between 50,000 and 70,000 miles from them. Another good tire for road and off road is the radial trep. Once they are broken in a little, they do great offroad. Also the MTR Kevlar. I think the KM2 is a little better in the mud than the goodyear though. The goodyear is better in the snow though. Hope that helps