One size does not fit all. My role model is a couple from SC that bought a new 45' Beaver DP and drove it to OR in 3.5 days to a Beaver rally. She was limping from breaking a leg snow skiing...they were both 84. At 73 I'm fortunate in that I can still out work most 30 year old...not saying much as most do not have much of a work ethic. I have no problem putting in 12 hour days behind the wheel of my DP...much easier than 12 hours operating heavy equipment. I still water ski and fly with no intention of stopping as long as I'm healthy.