I was back visiting my parents last week and stopped at the one in Slidell in the Hwy 190/Hwy 11 area, and it took us 30 minutes to get our order. I didn't care, though. They had onion rings and the ones in DFW don't.
I find the ones in DFW are quicker, but they taste slightly different, for some reason. Maybe it's mental. Who knows.