plug the hole
with the almost instant response from the current gps systems, i question the relevance of even having a knotmeter. it seems to me that it's more important to know what your speed over the ground is rather than your speed through the water - especially if you're cruising, not racing. i know that i'm not interested in the fact that my knotmeter shows 6 knots through the water when the foul current is only allowing me to make good 4.5 knots. if it were me, and it is me since i just made the very same decision, i'd plug the hole or just leave the transducer in and get a new gps.
