This place is pretty authentic, but it's not really the style of tacos I'm a big fan of. The tacos they serve here come in many varieties, but all are stewed sorts of things. You can wash it all down with a glass bottle of coca-cola made in mexico (way better than coke made here IMO)
I tend to like tacos with grilled things in them or done on a spit, like pastor (I guess that's more of a Baja and sonora style of thing). I'm not sure what part of mexico these tacos originate from, but i bet they're fairly true to form. I mainly give it 3 stars for that reason.
One other thing. They do have freshly made corn tortillas daily which is nice. You can buy packs of 'em.
Tip: you can park along the wall of the place for free. there are approximately 2+ cars lengths there so if there's a spot available its yours.