Stage It is a great site. The artist decides if there is a ticket price or if it's pay what you want. I've probably seen a dozen shows or so on there and have all been well worth it. It does depend on the bands audio setup and how they run it.
If this show is worth it will depend on how much you like the band. I usually only spend 5 bucks for these shows, so I prob won't drop 12 on this one.