Experience with Sikkens Cetol WB SRD stain

Sikkens has a relatively new water-based formula called Cetol WB SRD. My local high-end contractor store says it performs very well, and being water-based, has easy clean up, and has the anti-oxidants in the base stain, so it doesn't matter whether you use a darker or lighter stain, the same UV protection will be present.

Does anyone have experience with this stain? Does the color last--even in lighter colors like "Natural"? Does it go gray very quickly?