You're not going to find a better set of stairs than this one. The runway and landing are both perfect, smooth marble with absolutely no cracks. The runway and landing is both long and wide enough for any trick. The steps are more of a drop than anything, because the actual steps are small, making the gap rather insignificant.
This is the central detractor from this spot. Usually, you get kicked out within three tries by cops. Even if you don't, it's still a subway station, and there's always people walking through so you need to have someone watch for you in order to ensure that you're not going to crash into anybody. If a cop starts approaching you, it would be in your best interests to run, because it is a $100 summons and a board confiscation if you get caught on a skateboard in a subway station.
On 42nd Street, in between 6th Avenue and Seventh Avenue. Right in front of the Verizon Building, there is a black marble bordered subway entrance, and its right down those steps. Take the B, D, F, V or 7 to 42nd Street-Bryant Park and it's in the station, towards the 42nd Street entrance,