If we talk about speed, I have no problem in the western US in a car, traveling for hours in the 90 plus mph range. At these speeds and especially above this, one must understand the issues of closing speed, long stopping distances, extreme sensitivity to driver input, and the need to be looking a long ways down the highway. This requires a lot of driver energy input and full concentration.
The big problem for me at age 72 is driver fatigue. Pure and simple, driving at speeds less than 65 or better yet at 60, especially if in a GVWR of more than 10,000 pounds, is conducive to much better safety. And the slower speeds allow me at least, to pull for 10-14 hours, taking multiple rest stops, exercise, and naps several times during the day. My overall average speed for a day is about 50-53 mph, with two to four hours of stopped time each day. This seems to work best for my driving/life style.
Ms Tommie Lauer
2015 Serenity 30 RB / 2008 Dodge Cummins 4 X 4
WBCCI #4165 AIR #31871
Happy trails and Good Luck
Ms Tommie Fantine Lauer, Greensboro, NC
AIR #31871 WBCCI #4165 K4MTL