Some may make 500-600 miles a day (10 hrs) towing on our interstates and similar 4 lane systems but no one is gonna' make that kind of miles in 10 hrs on 2 lane highways that go through every berg on the road with the usual number of red lights/stop signs like city fathers like to see.
The last 540 mile trip we made was from CO to home. The A/C broke down which was no big deal in the CO/NM/UT mountains but with temps in the upper 90s/100s in KS and OK stopping for the nite was out. So we pushed on for 540 miles and 13 hours on without the benefit of the interstate system.