Finally I checked out this market. While its Chinese offerings aren't as extensive as 99 Ranch Daly City, it has a wide range of Thai, Vietnamese, Filipino, and other Southeast Asian items. I think it's on par with Battambang in the Tenderloin for Thai goods -- both MOM and Battambang have items that the other doesn't and both have pretty much all of the brands that Kasma (whose Thai cooking course I took) recommends. Produce is pretty good, and I especially liked the half-dozen types of eggplant. The biggest plus vs. Battambang is that MOM is clean, calm, and well-organized. It's a pleasure to shop there.
Be sure to ask for bags with handles when checking out. Now that the no-plastic rule is in effect, they usually use handle-less paper bags. Bags with handles cost 10 cents, or bring your own. Parking lot had open spaces as late at 9:30 am. Open 8:30-8:30 daily.
Manila Oriental Market
4175 Mission St, San Francisco, CA 94112