I don't know one from the other, but I do know pecans are terribly messy trees. There seems to be no time when they are not dropping something, sap, pollen, leaves and - of course - pecans. If you have a big yard and no pool, can plant it away from a patio or where it won't overhang a roof, it's a wonderful tree.

They are also VERY heavy water users. The nuts are often attacked by leaf footed plant bugs which damages the 'meat' inside. Pecan aphids sip fluid from the leaves in the fall and then excrete honeydew - a polite work for aphid poo. Its sticky and makes a mess of patio furniture or anything under the tree. Good news is that it's water soluble.

Just an FYI. ;-)

Here is a link that might be useful: Pecans in Home Yards

No kidding about that "aphid poo"! I really didn't know that was what the stuff really is; I just thought it was sap. It is really nasty and covers everything under the tree. I thought I wanted a pecan tree till I got up close and personal with the neighbor's tree.

Such well deserved negativity. I can think of no more wonderful tree that will prolifically feed you in September-October and provide dappled shade from its huge canopy and act as a primary canopy for secondary trees than a pecan. That said, it is not a tree for a pool or carport/patio underneath.
Choctaw (WS, usually plenty around the valley)
Mohawk
Pawnee (Mohawk)
Tejas
Western Schley
Mahan
should do well...some need pollinators (in brackets). Can order online in a few weeks.

What is the "WS" in your above post? I don't deny that the tree is wonderful in many ways, but it almost needs a yard of its own. The ones around here don't have widespread canopies; they're rather vertical.