T.T.
Lauren,
We had our daughter's 3rd bday at PIU Frisco (now one of the locations has a PIU Junior for younger kids - didn't have that then). It was great - you get your own play room and then your own party room. However, it was very expensive. The Frisco location only uses Papa John's for pizza (if you go that route) and it was soooo expensive. Other locations use cheaper pizza places. Then I was taxed and tipped on the total price - which was a lot. That was by far, the most expensive bday she's had to date (about to turn 5 and we've done one each year).
We attended a party at Wiggly Play Center on a Friday night. I don't know if it was the day/time but I think we were the only party in there (maybe one more) - and it didn't seem chaotic. I know the kids didn't care as much about the Wiggle time as they did playing. They had a blast.
I also recommend NOT opening gifts at the party - especially at this age. It's a beating and the kids would rather play than sit and watch gift opening!
Good luck!