PAT Central Market is a lot of fun, especially if you are white (because you can browse the aisles wondering WTF everything is!)
I come here more to browse than to actually buy much, but I do stock up on my fav Korean ingredients (Korean hot paste, kimchi, bulgogi meat, etc). I also sometimes come in here when the white people grocery stores are closed to pick up essentials like chicken breast and fruit/veg.
I'm sometimes not impressed with the overall cleanliness of PAT, sometimes it seems a little grubby/unclean, but this seems to be normal for most Asian grocery stores I've been to (with the exception of that giant superstore one down by the Docks)