The main thing I don't like about torsion bars is; they hang down too far and reduce ground clearance. Other than that I have no objection to them. I run about a 1.5" lift with them and have had it that way for over 80,000 miles. Many of those miles were off-road. I have not seen any wear problems on anything.
It was stated earlier that cranking the torsion bars up or down, increases or decreases the load on the torsion bar. That is not exactly true. Cranking the torsion bar up can cause it to be stressed more when flexed because it now can be flexed to a greater rotational angle before the suspension hits the stops. Under normal driving conditions torsion bars are not carrying any higher load when cracked up. In fact, they are probably carrying less load because raising the front will cause a slight shift in weight to the rear.
Cranking torsion bars to the extreme can cause problems if the geometry of the suspension and drive axles are beyond the limit of the design. That is why I only cranked them up 1.5". That kept the suspension at the maximum of the tolerance of the new ride height specifications by Ford.
2002 FX4 Bright Red Supercab 4.0 SOHC, manual 5-spd & Tcase, 33" BFG MTs, K&N air filter, Modified air box inlet, Gibson SS cat. back exhaust, Bama flash, Hidden Hitch round receiver, Rear helper air springs, Electric trailer brake controller, Line-X bed liner, WAAG bar with KC lights and Wildernest shell.