It’s really easy to adjust camber with the wheel off.
First, set your camber arms to the length I listed above when installing. Now you’ll barely need to adjust.
Before you put the wheel on, lower the knuckle onto a jack or wood block that puts that corner at about the same height as with the tire on.
Slap a angle gauge on the brake rotor.
Adjust camber.
Tighten all adjusters
Raise car, put tire on
Do toe adjustment.

I’d do the same with any camber arm, even if it can be adjusted with the wheel on. The N2itive ones are clearly a superior product, but the price difference is also very large. I’m willing to do the above process to save $400.

Of course, the stock arms are a fixed length and the reason we are replacing them is not variance, but just too much camber period. You can set your arms to 285mm hole-hole, put them on, get about 0.7 degrees and move on with your life. It’s not like getting each side within 0.2 degrees matters. If it did, we’d all be out messing with our front axle too.

Buy what works for you, but when the goal of most people is just to stop spending $$$ on tires, we don’t need to make this more expensive or complicated than it is. Setting camber is basically a one time thing for 99% of users of S/X camber arms.