Don't know where you are and everything varies from setup to location but i can tell you my experience.
Over here in Northern Westchester, I am completely overcome by the strong signal of Poughkeepsie Dispatch. Thats on 155.505. Sometimes when TMC is transmitting,the dispatcher will get stepped on by Poughkeepsie, the stronger signal wins in this situation and that signal is Poughkeepsie Dispatch, but thats only the Dispatch side of it.
On the "response " side of things on 154.92 i only hear transmissions around town and some surrounding areas. But Not every single transmission, i barely get them sometimes. I do occasionally hear cars in Putnam County but not very Often.
As Far as Car to Car Goes, i hear them alot around me and doing traffic stops around town. Again its very low signal if i get them at all.
Hope This Helps.