Lock the rear and LSD the front. A Detroit Truetrac LSD has no clutches to wear out. An LSD will give better overall performance ( combination of on/off-road ). An LSD will be easier on components in the front end. Remember, lockers are "low side finders". They tend to take you to the low side of your line when off-camber, on slippery surfaces, ect.

The LSD up front will make steering much better off-road than a locker. An LSD with an automatic tranny is a great combination. You can use your left foot braking to engage when a front wheel has left the ground. IMHO

As for the arguement that lockers and traction devices are cheating, here is my take. Learn to drive with open diffs. Install locker/LSD and learn all over again. Now, drive harder obstacles with the combination of skills learned. With lockers/LSD, others will watch while you wheel.