Came here to see The Weeknd during his King of the Fall tour with my girlfriend. The line was really long just to get checked by security.
As you get inside, the amphitheatre is huge and there are tons of carts selling beer. Two Canadians for $30? Wow. The lawns would be nice in the summertime but we got seats a lot closer because, for one, we really love his music and because there was a chance of rain that night. As others have said, be prepared to miss some of the concert when you need to go to the bathroom, lineups and trying to get through the crowd is a pain.
Overall, it was an amazing time except people with lawn seats actually tried taking empty seats that were closer to the stage a couple of times (happened when we went to the bathroom) but after you confront them they just move and find different empty seats. Other than that, it was an amazing experience and a must-do every year!