The Westerbeke is an old design. It's been around forever but the newer engines have taken new technologies and ran with them. It would be foolish not to take advantage of it. But, people on this very board have had critical things to say about the new Yanmars. It sounds like you're not among them. I would suspect that I could loose a hundred pounds and gain quite a bit of Horse power in the same engine space at a lower sound level and RPM. Have you found any down side to having your engine?