wow, i have never seen round subframes before.....i don't see how they can be as good as square ones........naturally by design the square box SFC will be more rigid. More room for flex in the round ones. Either way, have to be better then nothing I suppose.
I couldn't feel any difference when I had my fl mm sfc installed. I even made a thread about it, but even if I can't feel a difference, I know it's added structural integrity is well worth the cost.
steve, I had mine welded for $100 by a fellow mustang enthusiast. he did it in his garage and took about 4 hours.
I feel a lot of difference when I turn hard. Now I can go on this one freeway on-ramp at 60mph without braking. At normal straight-line driving, it feels well... normal.