I just bought a really nice 2001 Pro Line 23 Walkaround. The boat came with a 2002 Yamaha 200HP Saltwater Series II OX66 with about 500 hours on it. I have been running the boat/engine every weekend for the past two months without a single problem. My boating habits take me 20+ miles offshore for slow trolling for 4 to 6 hours at 900 - 1100 RPM. In other words, I do some heavy duty saltwater fishing. It's in saltwater 99.9% of the time. I want to re power the OX66 with a newer (used) 225HP Yamaha four stroke, circa 2004-2006. I have found several low-time motors for sale, but just can't bring myself to committing to the change considering the OX66 is still performing so well. The pre-buy had all the compressions normal, and the lower unit sealed. Can anyone give me some PROS and CONS of 1) re-powering and 2) keeping my current motor? The $ really isn't a factor. I am more concerned with performance issues (saltwater) with the four stroke vs the Saltwater Series motor. So, AM I crazy or what?