Thanks for the input so far.
Here's a video I recorded on a 2007 digital camera. The venue is practically identical to the one I'll be seeing the festival at (the one in the video is in Raleigh, NC, with the festival venue being in Charlotte, NC). This was shot from the very back of the lawn, right before the descending stairs down. Considering the camera, distance from the stage, and being outdoors, I'd say it was pretty decent. I've had MD recordings sound worse. Definitely room for improvement , but not distorted or anything like that. Of course, there's the chatters present in the video. I've never chosen a seat on the lawn based on noise reduction or the lowest noise level areas, so I'll be sure to keep an eye out for the stacks, as well as drunk, aggressive crowd members. Every show I've seen from the lawn at either venue had very clear sound with nice separation. So if all goes well, I should get a nice pull, if I can stay away from the drunks...
And yes, I apologize for the larger lady standing in front of the camera the entire time. I was working for The Sounds at this show, so I just grabbed a quick clip while I could.
http://www.youtube.com/watch?v=_nmLr7Ve73g
The only thing that the video clip tells me is that your camera works, which as most video camera's do today.
As far as where you will get the best sound, IMO, the best seat in the house will always sound better than the best sound on the lawn. The worst seat on the lawn will always sound worse than a good seat in the house. The worse seat in the house will sound better than the worse seat on the lawn. The worse seat in the house will not sound better than the best seat on the lawn, if the sound crew makes sure the lawn system is operating correctly. However, many times the sound crew does not do their job correctly and the repeaters are not mixed well, up in volume or working properly.
So, in general, it depends on where you are sitting in either place. That being said, I will not record nor will I even go to a show where I'm forced to record on the lawn. I've had too many experiences in the past where I tried, and had the best seat on the lawn, only to get poor results.
Also, for video, just because you have a 28 zoom does not mean you will get great or usable video from the lawn. Exposure time, apature settings, and video movement are all related. The closer you are to the source the better the clarity and stability of the video. Micro movements up close may not be a problem but back on the lawn become major movements which look like a wild boat ride on a rough lake.
If you are using one camera make sure you have it clamped to a stand and do not touch it for the entire set. Nothing but bad things will come from trying to zoom or pan during the shooting. Just get a nice tight crop of the band and leave it alone. That one static frame will serve you better than one which jitters, unevenly pans or at worst takes everyone on a roller coaster ride.