The Detroit TrueTrac is the only gear-driven LSD out there. I just got an email from TracTech today that the Taco TrueTrac should be out in about 6 months or so.

ARB vs Toyota e-locker is a sort of religious argument. It's not arguable that the ARB is more complex, with the air supply, the fittings, and the internal seals. I don't think you can go wrong with either, though.

I'd put a locker in the rear before you do the front. That difference will be amazing and you may rethink a front one. A front one has more limited use than a rear b/c offroad there are times you need to steer and a front locker fights that so a selectable ARB would spend almost all of it's time disengaged; onroad in ice and snow they are squirrelly unless you install an ARB.

I put a Detroit Locker in the rear and a TrueTrac in the front of my '94. It's a great setup offroad, but onroad in winter it could get a little (or a lot) scary at times. Two limited slips would be great for onroad, winter, and moderate 'wheeling.