Mmmmmm... Dim summmmm...
http://blogs.sfweekly.com/foodie/2012/02/san_franciscos_top_10_dim_sum.php
I love Yank Sing! I've never been super impressed with Ton Kiang -- and it always makes the top of the "best of" lists. We should try House of Banquet next time, RG! My friend loves that place and it's in my 'hood.
Yank Sing is probably the best dim sum I've had in SF proper, but as the Weekly's reviewer points out, it's pretty damn spendy compared with a lot of other dim sum places. Ton Kiang is admittedly not as good, but I have had a few really fine meals there--and they were on my side of town!
All that said, the last time I was in the bay area for more than two days, some friends took us to a place in Emeryville that was just incredible, every bit as good as Yank Sing imo. It's called Hong Kong East Ocean, and it's all the way out at the end of Powell Street on the Emeryville marina. Great location, killer views (if it's not foggy) and we *loved* our meal there.