Selectable lockers are always nice if the budget allows, detroits are stout and have been used and abuse in many rigs. The factory limited slip isn't that bad at least not the one I had. New clutches from ford with a extra added to it and man that thing was tight when on the skinny pedal. Make sure you set the gears up correctly or you'll have issues, if using existing gears run a pattern before disassembly so you have something to go off of in with your new carrier style locker as it will be different from the factory. Keep all your shims on each side together and measure as a starting point.