A couple of years ago I picked up a Garmin 310xt GPS watch to use to track my open water swims. A few fellow Southenders used other Garmin watches either in a Ziploc bag or just stuffed under their caps, but the 310xt was the first properly water resistant GPS watch that Garmin had made and liked the reassurance that that capability gave me.
Because GPS receivers perform poorly or not at all while submerged, the first thing I did with the 310xt was take the strap off and attach it to my goggles using some upgraded spring bars that I had lying around (the 310xt had notoriously flimsy spring bars). You can see the 310xt on the back of my goggles in the header photo for this site – the 2011 Trans Tahoe was one of the first times I used it.