I have gone to hundreds of these restaurants due to the fact that my SO is Chinese and all Chinese are food critics from the moment they leave the womb. The problem with these restaurants, is that their seems to be great range of quality depending on the chef you get. They do not exactly have quality control programs within these restaurants.
The othe funny thing about going to Chinese restaurants meant for Chinese, is that in alot of cases, the Americans do not get the same menus as the Chinese and many times it is mutiples times smaller. One time I got something not bigger than an index card when the week before when I went with my wife, I got a 16 page menu. LOL True.
I couldn't agree more. For example, I like New York Noodletown in Manhattan's Chinatown. But I've found that late Sunday night, the food is awful. During the week in the evening, it can be really good.
Someone once pointed out to me that the turnover in the kitchen in many of these restaurants is quite high, because they rely a lot on illegal immigrant labor, which is somewhat transient.
A friend of mine married to a Chinese husband once told me that she sends him into the Dim Sum restaurants ahead of her to secure a table, because the restaurant staff will seat him nearer to the kitchen, so they get the food while it's still hot and while there's more of a choice. There's definitely favoratism in play.