it is not a bad trans, as long as you keep the fluid cool the clutches will be good. also as long as the input torque does not exceed 500ft-lb it will hold just fine.
the largest issue with most dodge automatic transmissions is the use of improper fluids. While Amsoil, royal purple, and others are very good fluids, they are too slick and will allow the clutch pack to slip causing premature wear.