If I'm being honest I'm 1000000% more likely to return to PS than RW but that's personal preference. Queues to get in were horrendous, crowd was dead, site is out of the way to get to, drink choice was limited, zero nightlife apart from a naff DJ & food was unspectacular.
Though might have just been a bad year I went to RW.
EDIT: Also each act ever so slightly clashes so you'll always miss the first or last 5-10 minutes of the next set on.