Anyone ever used any of the Ultra Racing bars

I wouldn't really be that worried about pivoting at the joints in this context. The primary forces are acting along the the length of the bar, and not controlling/limiting the up and down motion between the two strut towers that much, which should be minimal anyway, based on how rigid this car is. I imagine that if the bolted or ball joints were that much of a blatant flaw in the design, at least mountune would be designing theirs differently.