I put one in the front of my daily driver a few years ago. The rear was an open D35, and I wanted to keep it that way till i changed it out.
Your right in that it will help pull you over things, better than a rear locker will. Ledges and rocks that I struggled with, became a walk in the park with the front locker.I found that it was more usefull than my buddies rear locker in most stuations. Steep hill accents does unload the front, but still I always had enough traction to make it. More than I had with no lockers. There is one hill in particular that I remember not being able to climb before the locker, that I could climb easily after install. It was loose dirt or mud, with off camber section right at the top.The nice thing about having the locker in the front, is the ability to hunt for traction by turning the wheel back and forth. On hill accents I found myself doing that more, than after adding the locker in the rear (which made everything easy). With an open rear you can also apply the brake when climbing an obstacle, that alows the rear to turn both axles a bit. This takes practice, but with a locked front, and the ability to apply some two axle power in the rear, you can get some pretty good traction. You can't do the brake trick with the open front (that 80/20 thing with the brake system).
So My opinion is that the front locker is better off-road than a rear, if you have to choose. My wheelin' is in the south, where we have "slick" as in muddy, rock, not that excellent traction surface they have out west.
The only thing about a automatic front locker, is that it will make noise in a dd that you will notice. Hard turns on pavement will bring a loud ratcheting sound, and will even play with the steering wheel a little. On the interstate at high speeds, and around town I never new it was there. Only time I really noticed was in parking lots making tight turns, or the hard left I made at the end of my drive-way. Not so much that you can't get used to it. Though new passengers will be asking what the H*&^ was that.
Driving a lok-rited rear XJ which was a friends, I noticed unloading effect. This would happen as you slowed to make a stop-light or sign. This would make the XJ want to pull to the left, then on unload, snapped it back to the right. Something you can also get used to, but more of a driveability problem than the front locker. That's the reason I bought a No-slip later for the rear, as they are transparent on the road, and excellent traction off road (they are a true locker, not a limited slip. Just a heck of alot smoother).
I used it with a front only for a year, welded the rear D35, broke the rear d35, and added a no-slip and an 8.25. The ratcheting eventually got to me and I installed lock-out hubs.
That said, if I started over again, I would have just done an OX locker (weren't available when I got started), or an ARB air locker. Expensive up front cost, but less in the long run if you don't want to run lock-out hubs.
I say the answer to another million dollar question is.... lock the front if your only locking one axle.
P.S. I noticed your in NC, so our traction problems are more similar than those of our western Brothers.