It's important to note that I don't think VIP tickets will get you into the main stage pit easier or into better position aside from the VIP areas. My personal opinion is they're not worth it, but that's for you to decide.
In the past they actually have gotten you into the main pit when it was full. Last year was the first year that they haven't allowed that as far as I know. The viewing areas are ok but they also kind of change every year. The Wookie usually has some sort of viewing platform that you can go on but it's maybe 50 yards out. the main stage has a platform sidestage that you're allowed onto that gives a pretty cool view. The problem is that these things are usually kind of crowded so it's benefit isn't as amazing as you'd hope. It's worth it if you wanna jump around between stages and not have to wait for a good spot but otherwise they're a bit overpriced
Last year was my first Sasquatch, but I saw no evidence that VIP tickets got you into the pit at the main stage. If they did it in 2011, there's probably a reasonable chance it's the same for 2012.