Pretty good experience. I'm not sure that we saved all that much through them instead of another avenue. We wanted to see Absinthe and there was a guy standing outside of Caesar's giving out vouchers for $80. And that's how much Tix 4 Tonight was also selling them for. The salesgirl said that the guy's coupon didn't include all the different taxes and service fees though. Who knows? I don't and I don't really care. Ticketmaster sells them for $124 so we were ultimately happy with the savings and the show itself.
There wasn't a long line at all to buy the ticket vouchers which I was sort of expecting. However, you do need to do the extra step and go immediately to the venue's box office to switch out your vouchers for actual tickets. Another slight negative is that you have no idea where you're going to be sitting. They don't even show you a seating chart. For Absinthe, it wasn't a big deal since the venue (tent) was so intimate but I don't know how one would fare with a larger show.
Another, albeit somewhat personal, negative was the girl who rung us up actually asked me if I was all right because to her, I seemed annoyed. Who says that?! I was tired and hot from walking around all day (it was like 112 at the time) so I probably wasn't being overly friendly but it wasn't like I was being rude to her or anything. Again, who says that to a customer?