It's not just the weight and length of the fifth wheel, other factors also matter. I work full time and have a young family, so a trailer for us is for camping and vacations and I drive my truck the rest of the time. In that scenario I'm willing to pull a larger fifth wheel with a SRW and it is a really capable truck because I don't want to deal with the drawbacks of a DRW. But if I'm retired and traveling more extensively the towing stability would matter more and the daily PITA factor of a DRW would matter less, so I'd lower the threshold where I'd go with a DRW.