Some of the food is 5 star, but the overall experience is a solid 3 or less. I've actually walked out 15 minutes after being seated and no one acknowledging us despite multiple servers walking by.
However, there are several pros. The chalupa is crispy and a perfectly balanced mix of flavors and freshness. The vegetarian fajitas have a great variety of vegetables. And the salsa bar is great. Being able to mix the regular salsa with chipotle and tomatillo allows you to customize your salsa exactly how you like it.
I've also had good luck with modifications to the menu. I ordered the pick 2 - chalupa and chimichanga - and the server accommodated me in making it vegetarian with grilled onions, pepper and other veggies.
I've read the bad reviews, but if you know what to order and if your service expectations are low, Tres Pesos is definitely the best value Mexican in the South Blvd area.