Sorry but I've been through this many times. I left karate 2 decades ago, quickly realizing (with in 2 weeks) that boxing and tai boxing are supirior. On top of the fact you need ground fighting, or at least some ground defence.
Lyoto Machida used karate moves but not in the traditional sence. He holds his gaurd like a boxer and mixses in tons of moves that are not from karate, thus karate on it's own is an incompleat style, that needs major changes to be effective! Just try blocking with one arm down in a street fight and see what happens lol. Andy Huges and Cro cop, are also heavy on the karate style, but again they both mod the style a lot for use in the ring IMHO.