In our younger days, about 8 hours or so was max - even with DH and his size 14 foot. Never thought I'd live to see the day he didn't fret over hurry, hurry, hurry. Yea, we've arrived. He's much happier towing about 55 - 60 or so and has mentioned many times that he'd never seen something we've passed a dozen times....well, no!, not at 80 mph! Now that I've started towing, he's really enjoying the trip. I enjoy towing and don't mind it at all....backing - not quite perfected yet. We've always thought that trying to cram too many miles into one day makes you worn to a frazzle before you ever get there. And daytime driving has always been our preference.