I'm sportin' K270's and i like 'em. They hook up well on dirt, float on sand, and i haven't hada pinchflat yet although i bottomed the rims on some rocks pretty hard. In the twisties, yeah, they squirm a bit but i found that to be the case only when pushing 'em hard. Fully loaded with camping gear the only did it as i got close to peg dragging. I wore out the sides of my boots which hit the ground before the pegs and it only started feeling lie i was at the edge of traction when i pushed it over hard enough to lift my foot off the peg when it hit the ground. If you hang off in corners you can get quite a lot of traction when railing twisties. For the extra few degrees i could get running a more street oriented tire , it's not worth it, the 270's let me get low enough.