I,m starting to look at used 5th wheels&at thier gvwr #. Who has current experience pulling with a 3500 6spd 410 srw, & has found the ideal 5th wheel weight for the whole U. S. &Canada area,I guess I,m wondering what price I'll pay for having the srw setup. I,m looking at 27'-30' single, & double slide models. I know it will pull real heavy loads but what's comfortable?