Let me give you a picture of Houston. If you stand on a 6' step ladder and look east, you can see New Orleans. If you look West, you can see Phoenix.
Basically, it is very, very flat.
That being said, you can't find a 250/350 - 2500/3500 within 100 miles with 4X2.
I am too old for boondocking and only tow a fifth wheel that we use in parks only. I would love to have a 4X2, but would have required either ordering from the factory or spreading out my search quite a bit.
There may have been 4X2 in the area, but the ratio in Houston area was less than 10%. Seems strange for a region that has no hills to speak of and rarely has ice on the roads.