Previously unrated boats aren't the only ones who get dinged in PHRF. I crew bow on a J-40 on the West coast of Florida and I can tell you that if you run a boat with any sort of racing pedigree in PHRF you'll also have to contend with some stiff numbers. For example, we rated within a few seconds of a 53' Beneteau First. Yeah, right.
I really enjoy the racing, especially in the company of crew and owners who are the right combination of competitive and fun-loving, but it soon loses it's luster when the boats you're sailing against in a beer can race are somewhere over the horizon either in front or behind you. Personally, I find pursuit starts and one-design more and more attractive.