I think this is a personal preference, but...

A 50/11 is a bigger gear than a 53/12.

On the other hand the compact will require more shifting when shifting rings up front, which might cost you a little time... also it would seem that a compact may be a little more prone to dropping the chain than the normal double espishilly with a 50/34.

My personl first choice would be a 53/39 double, than a 50/36 compact.

btw I don't race