I'm using 13:1 and HT motor with a 7.4v Lipo and have an 11.1v ready to slot in once I get the lacking of mosfet problem sorted.
Had high hopes after initially finding out about the Jefftrons but looks like I'll be waiting for the elusive spectre to show its face.
How you getting on with the Jefftron? I was looking at getting one of the internal ones that slot into the gearbox as I'm struggling getting a spectre but I was put off with it only rated for 20rps. I see you've exceeded that.