I'm on my second summer with the McGards. I set them by hand with a torque wrench to 80 pounds. Every month I recheck, they are always still at 80 pounds. They have never seen winter, but for the summer and a half they've been on the car, they still look like brand new. The key would be pretty tough to break if you only tighten by hand, which someone already posted that you absolutely must. I like the rotating seat too, keeps the prodrives scratch free!
I have no experience with the kics, so can't help there.