I would have to say that a traditional geometry 54cm will be WAY to small for you. I am ~5'11" and ride a 56cm with a fairly long stem. Keep in mind that this is a very general statement since there is much more to bike fit than your height. For instance, I have a long torso and quite short legs. (32" cycling inseam) So, depending on your build, you may even need to go to a 57 or 58cm depending on the manufacturer. Your best bet is to go to a local bike shop (LBS) and get a proper fitting done.

Good luck!
Bob