Interesting supposition and facts here.... while my opine is not factual, my installs on two G80's are. Plus I dont have a chip in the game here from a retailer standpoint so take this with a grain of salt.
When I got my G80 RWD- there was no KW and it was delayed until Oct 21 or around there so in May I decided on MSS. Now I have KW on my F93 and have had double digit sets of their HAS setups so it is my go to and still will be when available. But the MSS has shocked me with the ride quality and the drop level Ive done. Its linear set up really does soak up the bumps and edges while keeping the car very planted at speed. There is no extra bounce in its step which Ive had with other standard springs. Because I have other cars I dont always drive the X drive but when I do I really forget its lowered.
I am very very happy with these springs and because of that, when I sold my RWD car in Sept, I just moved the same set over to my X drive.
Of course these are my thoughts but they arent what I read or heard but instead what I can type and state. There are quite a few others here that will say the same thing about MSS. Full honesty, if both the KW and MSS were available, I would have got the KW. Hows that for bias or lack of it
X Drive
RWD