I agree with SadieKate. Know your own body, your local terrain, what you are capable of doing. I have a bad right knee/quad and I know without my triple I would definitely reinjure this old injury. I have to start each spring carefully building my leg back up but once it is strong again I am set for the new season with my triple. It is very hilly here where I live and I am 54 years young; these two factors plus my bum right leg make me just love my triple!

But you may be stronger, fitter, younger so you may be able to go with a compact. Try them both. Talk to friends other riders, lbs people. Listen to your own body and have fun!