My apartment faced the northern side of the building so I didn’t get the direct train noise but could sill hear them entering / leaving the station with windows open. Good news is that the sound proofing on the windows is pretty good and if you keep them closed you’ll be able to ignore it. Surprisingly, unless you have very sensitive hearing, you’ll get used to all of the city noises like I did incl. trains and ambulances down JFK at 3am and be able to sleep through all of it even with the windows open. If you have the choice I would take a northern facing unit for a bit of less train noise, some partial views of NYC and no big buildings blocking the light or views.