Try looking at it this way...
The wheel at the inside of a turn travels less distance than the wheel on the outside of a turn. If you understand how lockers and limited slip diffs work, they tend to bias more torque to the inside tire because it's turning slower. This causes the inside tire to pull or "drive" harder than the outside tire, which in turn wants to force your steering back toward straight (and is where the added steering effort comes from).
I think that if you added a PS cooler to your return, you'd be fine with anything but a spool or welded diff in the front axle.
If you're really worried about it, go with a selectable locker (there when you need it, not there when you don't).