After each side I do a stylus check with a 20x loupe mounted on a stand at the right height with focused back-lighting from a gooseneck Littlite. I suppose that is fanatical, but its now just a habit. I've tried a bunch of different techniques including the same AT vibrating cleaner, the small Last type brush, the Mr.Clean, and Zerodust.
With the caveat that it is not suitable for all cartridges, I've used LAST for over twenty years with very positive results. I think it mitigates the molecular level vinyl build-up that Doug mentions - though I haven't any molecular level evidence besides ease of stylus cleaning.
A fine sable hair artist brush with the tip clipped down a bit does an excellent job cleaning bits off the cantilever and motor mask. When more is needed for stylus cleaning I find the Zerodust gives the best and most consistent results with the least potential risk. Typically a single dip into the Zerodust is all it takes. Do it often and gently and there will be no need for more agressive cleaning. The Zerodust has a cover and is reuseable - cleans up easily with distilled water after a month or so of use.
Don't mean to sound like a Zerodust ad, but after years of using a bristly little brush (back to front only please) I welcome it as a safe effective product.
Tim