Replaced the Maxxis 2.2" tires that came on my Santa Cruz Chameleon with these (2.0") Contis, it transformed the bike. I mostly ride xc. These tires (with tubes) weigh less than the Maxxis tubeless setup the bike came with. They roll unbelievably better at the same inflation. (I also run these tires in a 26x2.2 on my '97 Santa Cruz Heckler.) These are ideal Summer tires for around here. Love them.
I use the Race Kings on a Trek Superfly for mostly gravel riding. The tires are great for gravel work - not sure how they would hold up on a cross country MTB trail. I'm on my second set & no problems with the tires at all - no flats & plenty of miles ridden before they show any appreciable wear.
As mountain bike tires go these are some of the fastest I've used.I am using them with tubes. These should be terrific for anyone doing flat cross country or not super technical courses. I recently did a fairly hilly duathlon that was mostly sand pinestraw and they were great. Anything much more technical I would choose a wider tire.
Swapped these onto a Trek DS for snow and trail riding. Great grip aired down a few PSI. Exceeds bike manufacturer width allowed but works perfectly. Great in the snow and mud.
I ride some basic local single track trails & dirt access roads. These tires are exactly what I needed to replace the road friendly tires on my dual sport. I now have adequate traction to climb hills without spinning the tires. If I don't have adequate traction, I probably need to dismount the bike anyway.
Chose these tires for several extended bikepacking trips on varied surfaces. They have met all expectations, rolling smooth and quiet on paved roads, holding traction on gravel turns and providing plenty of traction on single track. Some wear after about 1000 miles, but still lots of life.