This is a fantastic overall value, open late, and very tasty.
The store is located in a strip mall that is kind of sketchy. While it is on Las Vegas Blvd, I wouldn't really consider it walking distance from even the Wynn/Encore, which is the nearest major hotel. Also, when you come in there are various lines for different types of meat, but if you just talk with the cooks they'll help you out and get you what you want to order. You don't have to go to the right line.
Also, they offer free cebolitas, including grilled green onions and a jalapeno pepper, and also free pineapple with the spicy pork/adobada/al pastor (these are all the same thing here). You have to ask :)
The different meats also come with different sauces as defaults. So don't be surprised by that!
I thought the spicy pork/adobada/al pastor was by far the best, though I had no complaints about the carne asada either!