Expect there to be a lot of people. The concert will only bring more people, probally not to many more but it will bring in some. I was there 2 saturdays ago and it was crowed but cleared out nicely around 10. I got 2 rides on the beast in 20 minutes. Im goin on saturday and I know other than july 4th and 5th this is the only time its open til 12. The last few hours should be nice with lots of rides. Try to avoid the waterpark from about 1 to 6:30. Other times like right when it opens and before it closes are nice with lots of walk ons. Expect hour or more waits in the day on Face/Off, FOF, SOB, Beast, TR:TR, D-Zone. PKI is very easy to hit in a day though. A few tips, pick either to go directly to TR:TR and beast or Action zone when the park opens. If you pick Action zone go D-zone, Face/Off, SOB, Top Gun. Also, dont forget the beast at night, there is nothing like it. I might see you there if your around for last ride on beast.