Went to Joy Luck San Mateo for the first time on Sunday. We arrived at about 11:00 am. By 11:30 there was already a line. The space is quite large, but surprisingly noisy considering the very high ceiling. The clientele was about 99% Chinese. They serve the kind of food the Joy Luck "cafe" serves, noodles and small plates, but also dim sum, which came on trays not push carts.
We had mostly noodle dishes, which was comparable to the main branch, that is to say, very good. The prices are reasonable. The couple of dim sum dishes we had was also very good. Overall we did not have the time to really sample their offerings. But this certainly is a place we'll come back for lunch. I heard from a friend that their dinner prices are relatively expensive.