I also have YS 110 on mine. I tried the 16x4W. It spins at about 10k, but it does not seem to pull it as well as APC 16x6 @ 9500. Spool up with APC 16" prop is already marginal. I didn't try 17x4W because I think it's too heavy for crisp response, and 16x6 flies just fine. Here is a video of it w/ 16x6:

http://www.pedrofrigola.com/UCD3D&Stinger.wmv