We tried Mazi for the first time last week. We had gyros and the house retsina. I thought it was quite good value for the money. Will definitely go back - I can see it being a weeknight neighborhood dinner solution.
50 North is on 25th off of Blakeley. Yes, Frank's is owned by the people who own Pair. Melina's (the upscale descendant of Mama Melina's is at the corner of 25th and Blakeley. Shun is in the same building as Melina's, farther north.