I recently installed the studs from currie enterprises. 12MM X 1.5 X .610 KNURL and oem Toyota nuts. Everything is a close fit, I do not imagine substantial loss of concentricity. Tires could be out of round more than the ‘error’ induced by this method of mounting the wheels. I'll keep a close watch on them for the first little while. check torque. At this time, I doubt a hubentric spacers is required.