As both a huge taco person and a Southsider, I had high hopes for Tres Rios. The restaurant itself is quite large, and it's divided into two sections. There's a large bar, and a seated area.
I stopped by a while ago back when the place first opened. I had duck tacos, which came in a set of three. I found the tacos quite small and dry.
I think at that point Tres Rios was still experimenting with the menu, so I'm not sure if something has changed. The presentation was great, and the food looked pretty, but the flavor/combination wasn't anything that particularly stuck out.
Tres Rios isn't bad by any means, but with all the other unique and established taco places on the street, Tres Rios will have to step it up and bring something different to the table.