Hello everyone! I am happy to see you debating the concept here.
I just wanted to answer a few of your questions:
The reason why I went for Pol-Vari ND was that from the beginning I knew that an electronicly controlable aperture was not my field. So with e.g. a ND 0.3-0.6-1.2 variant that leaves you final adjusting your exposure at daytime with shutterspeed, since your ISO likely is set to the lowest possible. I didn't think that was flexible enough, and that would also mean compromising the shutterspeed which I wanted to be able to leave at 180 degrees. Plus - by always having that thought of "which one of those parameters do I want change know" you mind will be less present on the situation where you're at. And sure - all Vari-ND:s have flaws that can never be fully fixed, but I felt it was the best choice for people working fast.
Regarding color shifting (remember - all Pol-Vari inevitably suffers from this) please check out the HolyManta VND color cast test:
I'll try to stick around here to answer more question, otherwise send me a mail.