40 bux for Yok Rings....ouch

I run the single rings, and the camber is set to catch just a little of the outter rubber for some grip, finding the sweet spot is usually somewhere in the middle depending on the surface. Also, there are a few manufactures making Drift tires, in the end I think tire choice will depend on motor power and track surface...examples are

brushless w/ Yokomo HG's, Rings or HPI super-d's - any drift radials
or
19-27 turn with ABS, Odyssey's or any hard compound tire.

just my few cents tho, great write up