There isn't really much to add to what everyone else has said. Paul's Pelmeni is a great place to stop by for lunch or a big snack.
I recommend the combo with the works, a half order (~20 pelmeni) is usually good for 2 people for a snack or 1 for lunch. I like the meat dumplings a bit better than the potato ones.
The place itself is pretty small, but they have a few tables and I've never seen it get that crowded inside. I've only ordered take-out, and it seems like that's what most people do as well.
The service is quick and friendly, which is great when you just want to order to go.