we went July 2003 and would NEVER go back, it was awful.found it very noisy ,groups of teenagers hanging round , drunk til all hours, the showers were crap basically , not enough of them , cold , no pressure , exposed wires in the lights above cubicles where the ceiling panels were missing.when one block shut for "cleaning" a long walk to the next block and there was always a queue.This is a VERY large site.
On the positive side , a very good leisure / club facility , get there early on an evening for a seat if you like that sort of thing, plenty to do on site & stunning scenery nearby.
we went peak time so you may find it less hectic & things may have improved.
hope you enjoy it.