I used to fish JPG all the time, until I moved from Louisville to Bloomington. Now I have to drive from the north and that extra 40 minutes is a killer. If they'd ever open up a north gate, I might go back more often.
Anyway, the difficulty getting into the place is usually only in the spring. It has some nice-sized fish in it, but nowhere near what it used to be like before it opened fully (more or less) to the public.
The main reason I like to get there as early as possible is because you have to be off the grounds by around 4, which further limits fishing time (not to mention that you can only fish it Mondays, Fridays, and every other Saturday).

Louis