Pretty quality Mexican food and service. Restaurant is a bit dark (no matter what time of day) so just a warning. Prices are high - and there is an additional fee tacked on (couldn't tell if is was a partial resort fee but definitely and extra tax) and soda is served in small bottles so like every other Vegas restaurant wanting more than one pop costs you.
I had the 2 shredded beef crispy taco lunch with refried beans (lard is used in them) and rice, with a side of guac (not listed on menu so no idea of price until bill comes) and the husband had chile verde (came with side of rice/beans and his choice of corn or flour tortillas-he chose the latter). My tacos were yummy, the guac was good (not spicy and a good contrast to the spicy salsa that is served with the chips) and the husband enjoyed his meal.
My taco lunch was $18 and his chile verde was around $24. Each Diet Coke (3 in total I think) were $4 each and then add the guac and service fee and lunch was $75 before tip.
Aside from the price, this was the best part of The Aria Hotel.