I've driven your route (mostly) in reverse. Though I prefer OK-2 vice US-271 from Antlers to Clayton.
It's very good road, though it is close to 100 miles longer for your trip.
Another option is I-44 to US-75 on the outside Tulsa loop, down to I-40, west to Exit 231 at Pharoah, the south on US-75 to Atoka. Only adds about 30 miles to the trip length, and many fewer grades than on the eastern route via US-271.
OK-48 from I-44 to Durant is about the same distance, and not many grades. I've only towed on the stretch from Tupelo to Durant about two years ago when there was bridge construction. I'm planning to tow on it again in October.
Full-Time 2014 - ????
“Not all who wander are lost.”
"You were supposed to turn back at the last street."
2012 Ram 2500 Mega Cab
2014 Flagstaff 832IKBS TT