Are they worth it ?
I guess it depends on your thinking...
I thought they were...
disclosure:
Heim joints & regular street driving
sometimes doesn't work out well, can fail
BUT;
as long as you check them often,
I wouldn't worry too much, also carry a spare etc.
if you're worried about it
But they won't live as long as the poly bushed
or solid bars org. style bars, they are "generally"
meant to be alternative & light weight race versions
there is alum. non adj. solid versions
of the org. style or oversized alum. strut rods too
(I ran them QA1's on the street/strip for over 12k miles on my last RR
I had no issues, they were $219 for the pair back in 2007-ish)
there are different styles & brands,
even the type/style of Heim joint can be changed,
I only know of the QA1's shown, in my personal experiences
(I have a set {actually I purchased 2 sets of all the QA1 & SPC UCA stuff}
for my current project & a buddies too, just not sure I'm going that route yet)
Heim joints, it does free up movement,
many are adjustable too
but I wouldn't use them to get more caster {spindle angles}
just use for fine tuning/freeing up the LCA travel
"in a true arch & more exact geometry"
& is a little lighter weight difference, especially over the OE steel
In a racecar, where every pound makes a difference...
Weight reduction is far cheaper (at times) than more HP $ for $
