Nexus Neo/Ultra Si?

Has anyone tried one of these? It's got a rollerball for the P-tab, and all the reviews I've read say this is far and away miles above the "pinchy" tab on anything in the Aneros line. It glides over skin instead of pushing and stretching against it, which also adds to the mobility factor. They also say it doesn't quite hit the spot the way Aneros' do, being so tall (about five-and-a-half inches in length). My prostate sits really low (honest, I can reach the edge of it without even going past the second knuckle of my middle finger, especially after a month of SR), so I can't say how much this would do for me.

That rollerball is the most appealing thing to me, though.