[Helmantel]

I'd rather compensate the camber with shims rather than moving the ball joint. That way, the control arms stay the same length and you compensate for any shock tower variation from side to side. It may not matter much either way in practice though. An adjustable ball joint position also has the risk of starting to slide around unintentionally (but they may have solved this in some way?). Other than that, they look fine to me, judging from the picture.

Haven't used. Very familiar with the providing vendor. Interesting write-up in the NPD ad..... "camber curve has been optimized
by building Shelby Drop geometry into the billet aluminum cross shaft."
Mere relocation of the upper arm doesn't do a thing to "optimize" the camber curve. Dropping the UCA merely slows the arrival of
whatever camber curve is prescribed by the lengths of both of the arms.
Not crazy about the built-in drop cross-shaft. Would have to look at the material being used and figure strength of materials.
(SorT has that too but I know Shaun has done the math on his products)
There's no crossbar on the upper arm in the photo.

ex-Global West GM
1991-1995

I know you worked with this in the past but I don't see how dropping the arm wouldn't help the camber curve. I once calculated it for different scenarios. The base geometry has some camber gain, relative to the chassis, but it’s only ~30% of the body roll and the camber relative to the pavement will increase with body roll.
As I see it, both dropping the upper arm and shortening it can minimize the positive camber gain. The orange one has 1" shorter upper arms (just to see the effect).

 

[Helmantel]

I don't know either if the SPC arm is shorter. My example was generic.

I'm not sure if I agree with your earlier statement that dropping the arm doesn't do a thing. In my opinion it helps a lot and shortening the arm in addition can make it even better.

The arm's strength is another aspect and I'm sure (some of) the aftermarket arms are (much) better in this respect. Maybe I should try a set