: I put it on the water last night, it runs smoothly, and absolutely
: no leaks. The nose is not obviously digging in but it is not
: much/any faster than a plastic.
: Wondered if any of you can throw some light on what might be the
: cause?

Assuming you mean why it is not faster and not why it doesn't leak. Do you mean you expected it be faster because it is fiberglass?

Water doesn't care what material you boat is made of. Speed is largely related to resistance or friction with the water. Less wetted surface with mean more speed (usually). I build skin boats, 25 lbs or less but it that doesn't make them noticeably faster.

http://www.kudzucraft.com/articles/weight-speed/index.php