building at 210 East 35th Street

I also had the same questions. I actually visited these apartments and they look great. I would think the B line apartments are quiet since its in the back of the building.

Because New Yorkers who have the ability to make choices don't live in a neighborhood like this unless by mistake and then they move on as quickly as possible.

BEWARE! I used to live across the street from their building and faced the back of the bldg..however it was very noisy..cars honking when you get up in the morning and when you get home from work ugh! Despite "sound proof windows" btw there is no such thing only walls can be sound proof. Even facing the back the rise was unbearable it just bounces off the other buildings. I can't speak for this bldg but my friend lived in a newly an apt that also required her to pay ALL utilities incl heat/ hot water and believe me it adds up very quickly esp during the winter months it was the worst, she had to move. You would think they would smarten up and lower the rent to make up for all those utilities cost but I guess some of these landlords are just trying to squeeze people for every dime they have esp if their acts are sitting on the market for months- that tells you something is wrong IMHO. Good luck!

Becuase they move to this neighborhood to meet somebody at the local bars and restaurants, are wildly successful, and are married and looking for a place in New Jersey the following year?

No window beats a wall for soundproofing, and few owners of a rental would splurge on great windows.

But the right models, well installed, can be amazing. The triple-glazed windows I saw at 100 Jay St (2006 condo), and whatever was used at 70 Washington St (2005 conversion of 1916 building) cut the traffic roar of Dumbo's bridges, ramps, and roads to next to nothing, though 70 Washington's worked best only when a room door was also closed (leading to silence but stuffiness).