We usually hit the Valle Luna about once a week, and have done so for about the past 3 years. We don't do the restaurant, only the cantina for happy hour and some bar food. I'm not a big margarita drinker but my wife enjoys them and really likes the "Big Easy". I usually just have beer (Corona, por favor). Prices are really good.
As far as the bar food goes, it can't be beat for the price. We usually order a plate (6) of the mini tacos and share them. They're not really mini size and are more than enough for us, especially with the complementary chips and salsa.
Speaking of chips and salsa, first rate. The chips are always fresh and warm and the salsa is great. They serve a milder version with green chili, onions and cilantro or a hotter version that is red chili based. Both are good, but I prefer the hot stuff.