re: Frontera Grille
This is one of my favorite restaurants anywhere. On every visit, I've been impressed with the fresh and first-rate ingredients, the imagination in the preparations, and, simply enough, the way the food tastes. Especially anything/everything with tomatilla-based sauces.
The biggest down-side, by far, is the inconvenience of getting a table.
Incidentally, the frontera is a particularly good place for people traveling on their own -- the bar is ideal for a single person having dinner.