I've used various Krytox grease and oil grades for several years for my HW95 & R9 and have settled on the "plain Jane" GPL105, GPL106 for the oil and GPL205 grease formulas as best for my applications.........
The GPL225, GPL226 etc also contain an anti wear/anti corrosion additive, however I never had any corrosion issues with the plain GPL205 and a simple test over a few days proved what I suspected.
I took two degreased steel nails and coated one with Krytox GPL205 and left the other uncoated. Then I soaked a couple pieces of paper napkin soaked with a strong salt water solution and wrapped the nails with the wet napkin...........
I let the nails "soak" for a couple days and after unwrapping this is the result........
Since I don't normally soak my R9 or HW95 internals in strong saly water for a couple days I figured that the corrosion resistance of the "plain Jane" Krytox was adequate.
There is also an European alternative called Ultimox 226 which is based on Krytox GPL226 that's less expensive which I used for a while but I prefer the "Dupont offering".................
Krytox is a good but pricey "space station lube" that won't diesel or dry out like "dinisaur oil based" molly bearing lubes and Krytox isn't "black staining". Also, very little Krytox grease is needed to "keep things slippery"........
As a side note, Krytox GPL205 isn't thick enough to "kill spring twang" like slopping on "spring tar goop", but it also doesn't cause a springer to become temperature sensitive like "excessively thick "tar". I mentioned that petroleum based molly bearing "tar" also gets thick with age due the out-gassing of the petroleum carriers. Here is an example of my small tub of "heavy tar" that got so thick with age (even when stored in a sealed container) that it would support a socket head cap screw with a few threads embedded about 1/2 of the screw diameter..........