I stayed at their two bedroom apartment over Mother's Day weekend with my husband and parents. It was a great amount of space (two bedrooms, one bathroom) for all 4 of us. There is one master bedroom and one smaller bedroom. The kitchen was small but the living area was larger than the smaller bedroom. The only minor issue we had was the heat. It was a rainy weekend and the apartment got very hot during the night. We opened the windows, which helped but then the noise from the rain was pretty loud.
The location of the apartment was great. It was on the second floor in the back of the building. But the nice part was the convenience to Penn station. If you exit penn station from the Madison Square Garden exit around 33rd it's just three short blocks to their apartment on 30th. I was able to walk there with my luggage fairly easily. There is also a taxi line at penn station so it was a good place for my parents to get a taxi to JFK.