Hi ZD,Paul... did you have a try at wiping off the powdery substance?
As for difference in sharpness and clarity between SF and UVHD+, to my eyes it is a very minor difference, probably not noticeable without giving some close comparison to notice. The difference in color quality, the "view" as it might be called, is more readily apparent.
I didn’t try to use any product to wipe it down, just used my fingers to rub the powder. It did kind of wipe off, but I didn’t like it for over $2000. I’ve handled one of these at a local Bay Area where a birder had one and it had no clue of that. And the rubber was black, mine was kind of grayish. Maybe you could take a few photos of yours and post. Thank you..
To further the UVHD and SF conversation I’ll do more evaluations when I get the replacement. From my initial impressions and only from that first hour I’ll say this, if I was only allowed to choose one of them , I’d choose the Leica, not necessarily for the optics but because of how small, beautiful, compact and these binoculars have a punch in the view.
On the other hand because I’ll likely keep both (I fell in love with both optics) I would choose to use the SF for all day outings, more serious birding as the FOV is better, the focuser is a dream and the faster getting your eyes on board with the immersive feel. There’s not much optically that separates these two other than the form factor. One is real cool, the other is more of a tool.