WORST. VENUE. EVER.
It's oversized, over priced, impossible to get to, and impossible to get out of. It once took me 3 hours to get home from a sold out show there. And I lived in Manassas at the time.
The quality of concessions is below average even for a big corporate amphitheatre.
You cannot escape the corporate sponsorships as you are bombarded from every angle (much like at FedEx Field.)
The entire environment is stale and decidedly un-rock and roll.
Now, having said all that...the sound is quite good for an outdoor venue and the projection screens are good enough that even lawn seats aren't bad.
The actual concert experience is fine but the amount of frustration you'll experience before and after might affect the fondness of your memories.
If you really love the band, the quality of venue shouldn't deter you. But if you are on the fence, this is a really lousy place to see a show. If you go, take the afternoon off and leave an hour earlier than you were planning.