To continue a discussion started by Pat P. on the Manhattan board:
It's too bad you've been striking out so far. We tend to structure our trips to Philadelphia around the meals, and are rarely disappointed. I think it's a matter of your source. This board has some great tips. (And some even come from New Yorkers.) I'd be curious to know if you've had any meals at some of the places listed here.
I find that the Vietnamese places I've tried in Philly put most of the ones in NYC to shame. A particular fave in Chinatown is Vietnam Palace, on 11th St. We dream of our return visits there. Also, if you're a Pho fan, we love Pho Hoa, which is in a strip shopping center on Washington around 6th, I think.
We ate a very good meal last spring at Marco's on Vine. It did not seem a pale imitation of anything.
Hope you find some good ideas. (If all else fails, there's always the food trucks at the 30th St Station!)