salt water?
I did some checking on the Briggs and Stratton (AKA b&s) since I was in the market for just what they had. It's not only a warranty issue, but salt water will corrode some vital parts(like water pump) on this motor really quick compared to a motor geared for salt water. The design and accessbility of the controls seemed perfect for the 21 but I was planning a trip to florida the following year and knew I would be sailing on the gulf as well as biscayne bay. The 4HP 4-stroke that i ended up with was worth the wait while ups tried to figure out where it was damaged and sent it back to texas first (one of only a few E-bay disasters). You'll be happier with one geared for salt water, but if you switch between lake and tidal be sure to flush thouroughly before going back to the fresh water..