PST, Magnumforce, or?

I am looking to upgrade my upper control arms to tubular. CAP is not being considered. The PST and magnumforce look the same. Anyone have experience with these? Are there others to consider? I have the 73-up disc setup on my 66, and I am looking for more caster. I already used the offset bushings, but can barely get 1 degree pos caster. Since this is a drag car, I would like some more positive caster for stability.