The other reviewers have covered most of the stuff (great variety of Korean foodstuffs, not-the-best produce section, frozen everything), but I like PAT Central Market because it carries items for more health-conscious Korean food eaters: Everything from additive-free soybean paste to brown rice powder for making rice cake to mugwort powder - stuff I haven't been able to find at the shinier, sparkling H Mart.
I like it!