I have only used a SS Level 2 stylus on my 501 since buying it used: under a microscope it the original stylus showed a lot of wear and the seller kindly and immediately paid for a retip. Pretty cool.
So: the Level 2 is revelatory for me, particularly against the elliptical styli Shelter likes to use. It simply gets into areas of the groove that haven't been played before, and reawakens a lot of older records I'd written off. I really am an adherent of the Level 2 upgrade because its profile isn't as severe and difficult to line up as the Shibata Level 3 tip. Hope this helps.
So: the Level 2 is revelatory for me, particularly against the elliptical styli Shelter likes to use. It simply gets into areas of the groove that haven't been played before, and reawakens a lot of older records I'd written off. I really am an adherent of the Level 2 upgrade because its profile isn't as severe and difficult to line up as the Shibata Level 3 tip. Hope this helps.