My opinion of Quigley going to C channel is so that the arm will flex (twist) easier than a tube version, which causes the weld to fail sooner. The axle swings on a center axis. The closer the upper and lower arms are the less they twist. Bushings can only flex so much. They are there for the dampening of the bumps and to allow minimal flex. A leaf axle has the benefit of allowing the leafs to twist and assist in the articulation of the axle. On a leaf axle the front and back bushing twist in unison to each other, unlike front arms twisting against each other. I do not believe the "Q" set up was really designed for excessive wheel travel hence the short arms. the best solution for the "Q" suspension is Heim joints at each end or at a minimum one end of each arm. Since I did my own conversion and do not have a "Q" set up or any other after market set up, I built 2"x.25 walled with inner 1.75 x.25 walled chrome moly tubing with 1.25" racing heim joints. The heim joints will hold the axle mount point and articulate at both the axle and at the frame mount. "Q" Factory replacement arms will only break again so all you are doing is kicking the can down the road. Good Heims are well close to $100.00 to 125.00 but it beats breaking in the boonies. To add I had a Jeep that I converted to the early Bronco radius arm style front Dana 44 axle. These are factory cast arms. After 10 years and 20 or so times thru the Hammers, I snapped those arms at the base of the arm where the C's mount to behind the axle. Yes both at the same time. The odd thing is if you are familiar with the radius arms they have a threaded end for a round (donut) style bushing at the frame mount so the arm can rotate/twist side to side like a pencil in a sharpener. The Jeep had 14" to 16"s of travel so when one side dropped in a hole and the other climbed, the axle needed to twist. The top side of the driver side wanted to roll forward and the passenger side back. Since those are 1/2'' wall axle tubes the C's were continually stressed. Even with the C bushings for cushion the years took their toll on the weakest point, the arms.