Minnflyer did a review of the Goldberg Protege which is about the same size as the one you are planning on for the OS 55 AX engine. He used and recommends the OS 55 AX on the Protege and it pulls that plane around pretty well. Here is a link to the review. Take a look for yourself.
http://www.rcuniverse.com/magazine/a...article_id=901