Had the KR21s on a year. Bought these on price and the treadwear number. The wife put 42K on our new '08 Santa Fe in the first year and the factory Brigestones were junk (little tread remaining, max noise and no traction) by then. The KR 21s were a world apart! Smooth quiet ride, very good wet & dry traction, suprising winter traction too. Had NO PROBLEM handling the big snow storm in Dec '09 that hit the Interstate(s) 64, 81, 66 area in Virginia & West Virginia. Seemed like everyone pulled off the road... we kept going right through it and even crossed WV on US 50. It looked like we were the only 2wd I saw moving all day. But I don't credit just the tires; some was my experience and some credit goes to Hyundai.
At 30k on the KR21s started to get a little vibration above 70mph. Rebalanced on the next rotation and NO MORE vibration! 35K Right now and the KR21s are measuring 50% tread from when my UPS guy dropped them at my door. I [faithfully] rotate every 5k and measure tread deapth across all tread grooves in two (2) places on every tire. I use those masurement results to adjust the air pressure as needed to ensure even wear across the tire. I don't go to tire shops--I mounted them, balanced them and do all my own work since the nearby military base has a fully equipped auto hobby shop that I can use.
I've (wife and I) have worn out lots of tires (all brands) over the last 30+ years and these KR21s are now starting to look better than any we've ever owned. The paperwork that came with them said they were rated at 85K for mileage. I doubt we get that because I don't run tires down to 2/32nds (the wear bars.) I start shopping 'bout 5/32s and buy around 4/32s. I'll get 60K and be a very happy camper!
It's a shame an American company can't produce someting like this--at this price point. Unless they pull a rabbit out of their hat(s)... I'll likely hit-up TR for another set of KR21s next summer... or sooner if the wife doesn't let-up on the mileage.