Well, the biggest difference is the surface contact. A 1/4" set screw has less area to contact the barrel assy compared to the circumference of the chamfered end of the arbor. Kinda like the difference between 18 gage wire and 10 gage wire. (Lamp cord vs jumper cables).
Pluse, if I use the set screw for the arbor length correction, it does away with the adjustable forward wedge bearing. I like having options.
(Good move using the shims! It looks better than junk glued to the end of the arbor!! Lol)
Mike
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