Not bad -- of all the 'East Chinatown' Vietnamese joints, this probably has the friendliest service from the Cantonese speaking ladies. And, oddly enough, has a large rainbow flag decal on the window.
I've had the dac biet (house special pho) twice here. The pho broth is very light in colour but packs decent flavour. However, I felt the beef bits subpar -- these is no rare beef and everything comes fully cooked. I would suggest going with the pho tai or asking them to have the rare beef on the side.
I have to give the edge to Bach Yen for my favourite Vietnamese joint in East Chinatwon, but Mi Mi is a decent alternative. Drop by here because my girlfriend prefers the vegetarian options here.