I have a few watches but like a few others, I prefer to go the cheap and replaceable route when sailing. My sailing watch is a Casio Sea Pathfinder (which I believe is a cheaper version of the Pathfinder). Waterproof to 100m, back light, alarms, tide graph, stopwatch and dual time. Gains one second every 5 days which is easy enough to keep track of. Has taken a few years of some tough punishment. Don't know how much it cost because I got it free with a magazine subscription.
If I lose it, no big deal...