since i am newb to suspension engineering/design I'd appreciate some elaboration on your comment.

seems like the SPCs are delivering good results on a lot of cars here. the SPL looks very well designed but also like overkill for the average, casual track guy (2-3 HPDEs and about the same autoX per year.)

It's some basic mfgr/engineering concepts. I am no pro in either unless you want to talk about databases/software engineering lol.

but the idea is this, the SPC and Kinetix arms are both a " rod, loaded in sheer" design. I have no idea why someone would do this for an auto part.

That rod/bolt looking thing that attaches to the spindle is compressed in sheer. Think about if you wanted to break a pencil in half with your hands, what would be the easiest way to do it? Load it in sheer.

Now instead of the easiest way, what would be the most difficult way? Loaded it in compression.

If you took that same pencil and put the eraser near your palm, and the tip near the tip of your middle finger, it would be loaded in compression-and very difficult no matter how strong your arms and hands are, to break.

now look at the SPC/kinetix Rod(pencil) it's that little threaded 1/4"? rod , and it's loaded in sheer.

now look at the SPL camber arm, it's nearly an inch of steel, with a rod, loaded at 90 degrees in compression with a washer.

The truth is you are pretty unlikely to die at an autoX event. There's not a lot of sh1t to run into besides those kittens that live under the cones.

On a road course, it's really not hard to kill yourself. If I am going to kill myself, it's going to be because I was trying to drive my car too fast, not because I was too cheap to spend 400 dollars extra for a quality piece of equipment and my effing camber arm snapped like a pencil.