My usual pollination technique is to take a coated fingertip (and usually a few anthers), stick them into the middle of the bloom, and rub it around a little. This obviously won’t work with my Single Musk, or any rose with similar reproductive anatomy.
What methods have worked out for you?
When in doubt, there is always the old paint brush technique. I’ve used it on Stellata mirifica and Minutifolia with apparent successes. Why not for Synstylae? Rubbing a heavily coated finger around the tops of the fused styles should work, but a loaded paint brush (though possibly using and wasting more pollen than a finger) should flood the tips fairly efficiently.
My preferred method (Synstylae or otherwise) is to use an actual flower itself as the paint brush. I typically will bring inside several flowers of the male parent that are just about to open, and remove the sepals and petals from them. I lay the little “brushes” of stamens on a small mirror (usually overnight) until I need them to do a pollination. I can usually get quite a few flowers pollinated by each little disposable brush. I used this method this Spring with the little flowers of ‘Plaisanterie’ and know that they’d easily numbered in the hundreds (or I guess maybe thousands) by the time our hybridizing season was winding down. I typically prepped two dozen of these a day and kept them drying/dehiscing in a little boat made of aluminum foil. Then I made my rounds with the “boat” and pollinated all the waiting recipients. This went on for weeks on end. It’s going to be an exciting Springtime 2017 
Good luck with your Musk crosses. It definitely needs to be used more in crosses. I just planted a new Single Musk this Spring and hope that it’ll overwinter well enough to use it next year.
Thanks, I was trying to steer clear of the q-tip approach, since most of the pollen parents I’m working with are very stingy, but will try both of those right away. 
I use small beading jars. The anthers are cut into the jars and left a short time till the pollen is shed and then I shake it vigorously causing the pollen the coat the glass. Then I take the lid off and use the lid as the actual applicator. Because it’s glass I can see the stigma rubbing through the pollen and I never have to touch either the pollen or the stigma. Works for stingy pollen producers as well as you can see the pollen very clearly against the glass and then just use the stigmas as small brushes to collect the pollen. Ignore the numbers on the photos. They were made as part of a series to help people on my old Rosetalk Australia Forum. [attachment=0]pollination7.jpg[/attachment][attachment=1]pollination6.jpg[/attachment][attachment=2]pollination4.jpg[/attachment]
