Went with the full spraysuit and lots of "Frosty Fleece" underneath (built and sold here in FL). Was warm, but didn't stay out long on the water ("minor" incident with other boat).

For me, the cold certainly takes a bit of fun out of the sailing, because I have to spend more time piling on more layers, and I'm less likely to sail to the edge of performance, because flipping with be very cold and I won't be able to swim as well with all that crap on.

Still, I'd venture out on a cold, sunny day as long as the wind wasn't howling...

And just what was the windchill with 40 degrees and 30 kts?