Re: Quick question from MTBer thinking about first road bike
I'm 5'11 (and a half!) and rode similar sized Kona's for years and when I got my first road bike I got a 56cm frame. The best thing to do would be to have a trip down to your LBS, as they'd give you a pretty good fitting and advice. If you're buying on line, you could put in all your details onto the sizer-upper thing on Canyon's website, that takes into account height, leg length, arm length, size of your current television set and length of shoe laces etc.etc.etc....
Good luck with it!