Flying with an unfilled weave?

Hello,

Has anyone seen any data/research showing the performance gains of
filling the fiberglass weave of a composite aircraft such as a KR-2?

For example, if a KR is built with a RAF-48 or NACA wing
(non-laminar), if layups were done over a smooth substrate (smooth
foam), and the weave of an "average" weave glass was left unfilled
(after peel-ply), how would speed be effected? Dacron-covered planes
of course get by with a bit of weave showing.

If the cruise speed of a given KR-2 was 120mph "filled," any idea on
how
much slower it would cruise if left bare but painted?

The looks would probably suffer, but how about performance and safety?
All opinions and ideas are welcome.