I believe there is a vendor thread here somewhere, but I'm not sure how best to find it, so I'll just say explain what I got and why. I got their "Alignment Kit 1." It is a kit that includes three sets of components:
1) Lowering links: these are parts to make the vehicle run lower by changing the connection to the height sensors on all four corners which should prevent and/or reduce shudder. These are adjustable and not necessary if you are anly concerned about tire wear but not concerned about the shudder. I've had the shudder TSBs performend and would prefer not to continue replacing half shafts, plus I figure running lower might have a positive effect on efficiency. I believe I've seen others here with the lowering links indicate they are seeing better efficiency using them.
2) Adjustable rear camber arms: These replace the fixed rear camber arms and allow camber to be adjusted during alignment (the factory arms have no adjustment). While I am told that toe has a larger effect on tire wear, my inner tire wear occurred in spite of running standard height with frequent alignments at the service center.
3) Adjustable rear toe arms: These replace the factory rear toe arms. I'm not sure if the rear toe arms are fixed or not, as toe is adjustable, but that doesn't mean the arm itself is. Either way, if I remember correctly, these provide for more (and possibly finer) adjustment, while running further lowered likely makes more adjustment necessary to have good toe settings.
Regarding your warranty question, the home page for n2itive is Eliminate Inner Tire & Premature Half-Shaft Wear On Tesla X/S! and it includes this practically boilerplate comment that a lot of aftermarket vendors (and forum gearheads) point out:
That having been said, my service center indicates they will not install aftermarket parts, so finding an installer was a big hold-up for me getting these, and I had to decide I really wanted them before I was motivated enough to do that. You might not have as much concern on that front given your location (I believe there are plenty of options in the peninsula, and I assume the same would hold true for the bay area). At my most recent service center visit, the advisor I spoke with indicated they do alignments for multiple customers with lowering kits installed, or at least implied that they do by indicating the alignments were more difficult. Given the ease of alignment and improvements claimed by n2itive for their newest kit, I'm guessing that increased difficulty may be specific to other brands and/or lowering kits without alignment kits, but it could also be due to lack of knowledge about the parts or some rules and procedures followed by the service center.
