Summary: Good steak tacos. Good guacamole. Reasonable prices.
This place seems to have a worse general opinion than it would otherwise deserve. Granted, it's a food court in MGM with a bunch of other places, but really it did not come off as being significantly worse than what would be expected or desired from such an establishment in such a location.
I ordered the steak tacos, which were reasonable priced, tasty, and excellent quality. There was no gristle or under/over-cooking and the tortillas were nice and toasty. The salsas available complemented well, and the guacamole was also pretty good (albeit a little citrusy). The whole meal cost about $15 and was definitely filling. It's not the best Mexican food I have ever had, but it is far from the worst either. Certainly worth checking out.