There's a guy here in Colorado who can build a monster 4EAT. A friend of mine has one in his car. Totally driver controllable shift points. Lights it up in 3rd gear if he wants to. But we're talking something like $6000-7000, which makes for a very limited market.
Hell, people hear that a front diff for the box costs $1300 and they run and hide. I don't think it's a matter of there not being people out there who can build a good EAT. It's more a matter of there's a very limited number of people willing to spend what it takes.