Yes. Get the killer deal. You can fit pretty easily one-up or one-down. When you look at it closely, the difference between a 52 and a 54 is about 1/2 of an inch. If you feel best on a 54, you can easily fit on a 52 or a 56. Bikes are built to be adjustable. Too many people here get all wrapped around the axel on having a specific, perfectly sized bike..like anything off by 2cm will cause horrible bodily harm or something. I started out on a 54, found a KILLER deal on a 56 and got it. Bought a shorter stem for $20 and I was riding in the exact same position I was before. Then I upgraded and found a killer deal on a 52. Put a longer stem on it and everything is great.

If you are looking for a new bike, don't pass up a great deal because it isn't what you think is the perfect size.