Now I say "don't do this" because we started with the absolute best experience we could have and then sampled a low end event ($35 per ticket) last night. Although many found the event to be a big value - all the margaritas you could drink and all the appetizers you could eat - the quality was so stunningly inferior when compared to our first night that it just ruined it for me.
The Mexican food served buffet style was mediocre at best and you had to stand in line for it on the concrete floors of The Vault. It was crowded and we had to take a break during the evening and walk along the River Walk. The best part of that evening was that a time share company from Cancun (I believe that's the deal, anyway) was handing out Rick Bayless cookbooks for free. And, the band was excellent.
The moral to this story is that you get what you pay for and if you want consistent quality from evening to evening be more careful than we were.
I've decided that I will stick to "sit down" dinners with reputable restaurants and wineries. I have to say that the Mexican food served at Lo Mejor de Mexico, was not Lo Mejor!