To be honest, I'd use PLA. Technically, ABS has more tensile strength and in the engineering world is considered the stronger material. However, this is not what you want in this case, You want a material that is harder/more rigid (PLA). These will work on even the worse quality rods. Whatever you use to hold this bearing, make sure it's adjustable. You can use this adjustment to collapse the printed bearing to accommodate slightly different diameter in rods. Print it in ABS or PLA, you'll be fine. Bottom line- the ABS might have more flex in it but will last longer: (14+ months plus).