Now that it's not Chinese New Year, I made it to DC Sandwich today (Rte 50 nr Loehmann's Plaza). It has its strengths and weaknesses.
Banh Mi made (of course) to order, $2.25 to $2.75 (sandwich only), with sandwich-drink combos priced higher. Also available: Euro-style pastries, Viet-style pastries, an array of chilled by-the-pound Viet specialties (vegetable and meat, I think) and, behind the counter, more hot ones (also "I think"), plus a franchise cart/fryer/filler that makes filled pastries available by the box.
The sandwich bread is baked right there, and it's delicious (longer and softer than the loaf in common use elsewhere) - I'd love a bag of the rolls to take home for dinner, but for banh mi I prefer the loaf with more "tooth" that I'm used to from Eden Center. In honesty, this MAY be a repeat of my tendency to prefer the sytle I first fell in love with of any food I like.
All the usual varieties of banh mi are available. I got the meatball sandwich, and found the ingredients fresh and well-balanced, but it was too generously supplied with mayonnaise. I am a big "gooey sandwich" fan, but this was on the far side of what I like in banh mi.
I may visit again, especially weekends when Eden Center threatens to squeeze loose cars back out onto the highway like toothpaste out of a tube, but I'm happier with the banh mi I experienced first.