One thing to keep in mind: Leaf springs have compensators with bushings that wear out. If you are one to check them, you might be replacing them periodically. You might detect play in them when examining the trailer...only with the side (both wheels suspended) of the ground. No chance of that play with torsion suspensions.

I have used a compensator style with car trailers for years. Now I have torsion on a camping trailer. No other complaint with either.

Bill