I had a chance to use my new fingerless mitts from Black Rock gear this weekend.
http://www.blackrockgear.com/foldbackmitts.html
I did a quick trip to Cottonwood lakes in the Sierras with a summit of Mt Langley. Temps were down to 21 with snow one of the nights. Daytimes were 40-50's and super windy so these down mitts got lots of use. The foldback design is just brilliant! It is really easy to pull a few fingers out (without the other hand) to use them for turning pages on a book, using the camera, operating zippers, putting on chapstick or using my iphone. And then just as quickly pull them back in. The fit is really good. A little more contoured compared to the plain BRG mitts,resulting in being more snug and staying in place well. They also seem to have more down than previous generations. These things really puff up and feel densely packed. Super warm! Held up to the wind quite well too. I didn't notice an drafts or anything coming through the slit where they foldback. There really isn't any drawback to the foldback that I experienced.
Overall, I couldn't be more pleased with how these worked. For those who already have the original BRG mitts, is it worth upgrading? I think so. Because you are so functional with these gloves. That and they are warmer and fit my hand better. In comparison to using wool gloves or something like that, these are a lot warmer, and probably still more functional.

