rt ...
I think your question can best be answered with a resounding ... they run the gamut of all levels of college play. Some leagues garner players from predominately major and mid-major D-1 programs, while others have a wide diversity of players from all levels of college baseball, including JUCO. Heck, some teams even have players who are out of college and looking for a spot on an independent team. So, there is almost too much diversity to generalize.
One thing is for certain tho ... the wood bat definitely changes the game for these players. It offers many pitchers an opportunity to get more innings at a higher level of success than they might see against aluminum bats in college. And the hitters often change their approach after the wood bats of summer, bringing added success in college. JMHO