Being from San Diego, I've missed good Mexican food. A few months ago I tried out Taco Loco also and they are passable. The food is a bit pricey for what it is but was but was a welcome change.
Haven't had Mexican food in China... only in Hong Kong. Both Kevin and I grew up in Socal and as such can be picky about our Mexican food. I guess what it comes down to is the meat and seasoning. If they don't get the right cut, marinate it the right way or cook it to the desired wellness, it's just not going to do it for us. Oh, and the price has to be right.
In Hong Kong, I've tried Taco Loco (soho) and some place that doesn't exist in East TST anymore. Of them, Taco Loco was the closest to being passable. It was basically mediocre taco shop food at twice the price.