I have found that the longer the tongue, the easier to control while backing. I imagine that the distance between the hitch and the trailer wheels is the real distance that is important - that and the possibility of hitting your rear bumper if the turn is too tight and getting the back door all the way open with the trailer attached.

89 3L V6 5spd SWB, Aisin Manual Hubs, 2 (suspension) seater Raider in Wheeler, OR