I just got a takeout pork bun from Yank Sing 2 Go on Stevenson Street in Downtown SF, and I wasn't that impressed. The bun stuck to the wrapper, and it wasn't super hot, but those things were to be expected from a bun that had been sitting for a while. So, no big deal.
But the filling of the pork bun wasn't that good at all. It just tasted like some bits of bbq pork (same as what i'd find anywhere) with a heavy douse of hoisin sauce.
Is this the same filling they use at the actual sitdown restaurant?