I know, for sure, that I have eaten at Polonia's and I am also pretty sure that I have eaten at Under the Eagle, as well (I have dined at 2 places in Hamtramck). They are both fabulous. One of them (Polonia's, I think) had FABULOUS dill pickle soup and cheese nalezniki (spelling?) and cheese pierogy (my favorite!!) and my dad loves the czarnina - As I recall, these 2 places were close by each other - possibly both were located on Joseph Campau, but I am not positive (don't know if I spelled the street name correctly). In any case, you can't go wrong with the Polish food in Hamtramck!
I live in Canada, but have relatives in Michigan (my dad is from Hamtramck) and we go there whenever we are in the Detroit area, which is not often enough.
Another good place to eat was, I think, called the Polish Cultural Center, but I don't remember where that was - maybe in the Sterling Heights area? A Michigander could verify the name/location. It was like a legion hall - yummy, yummy food!