I'm considering using a Twin I Beam in my '48 Chev project. Mainly because it came with the '94 F150 I bought to get the fuellie 300 six. I have a Camaro clip, but I like the bigger brakes better on the F150 if using 15" wheels.
It looks to me that Ford compromised the steering linkage some when they designed it in the first place and this may be some of the cause for the tire wear complaints. The tie rods should originate from the axle beam pivot axis to avoid bump steer and changes in toe as ride height changes with vehicle load.
Camber changes with suspension height change are not so bad as long as the normal ride height camber is correct. Un-equal A Arm suspension also is designed to increase negative camber as the suspension is compressed. When the body rolls in cornering the camber changes relative to the body but stays fairly constant relative to the road. And actually when turning left you want some decrease in camber on the righjt side and increase on the left.
Another feature of this suspension not mentioned much is the "anti-dive" effect during breaking resulting from brake torque acting on the trailing arm which attempts to lift the chassis. This feature is lost and in fact reversed if you replace the trailing arms with parrallel radius rods.
Lowering the car with the '94 axles might be a challenge. I'm thinking I'll build special frame rail sections with windows so the axles pass through the rails instead of under. Will likely have to mount the engine higher than normal as I haven't figgured out how to window the crankshaft.
Wish me luck