Im not sure if it is sweat because it started a few minutes after the rain began,(it was on the back leg of the journey), whils during the journey to heligoland, i had no problems whatsover despite the sun. The drysuit is maybe three years old, or four, we bought it new while it was on sale.
We've had this issue before, but only when it was either raining or there was a lot of spray.
When boating over longer distances i much prefer a drysuit, if you fall in, you can just climb back out.
Searider+Yamaha+Land Rover= :D :D