Ray Parkerhurst on another forum has done extensive stacked-image photography of stylus tips including accurate um measurements of the facets and degree of alignment accuracy. He'll image yours for free if you send it to him.
For me, it's particularly interesting to see new tips and their facet measurements. What we might think of as a .3 x .7 elliptical or a .2 x 3 line contact are often something quite different in reality. And if you think most styli are aligned with perfect accuracy on the cantilever, stacked-image photography will be quite an eye-opener. 2 degrees to 3 degrees of diamond misalignment is not uncommon. Line contact tips with one line half the length of the other, left/right sides not quite 180 degrees apart, and so, so much more. Some manufacturers are extremely precise and consistent. Many of the "NOS" or "barely used" styli he buys are badly worn and he documents that well. It's interesting to see how different tips wear over time.
Let's say you painstakingly align your cartridge properly, aligning to the cantilever under magnification and using a fancy protractor. If the diamond is 2.5 degrees off, how accurate in reality is your alignment? Being practical, if your alignment is a few degrees off because the tip is mounted a few degrees off, and anti-skating is what it is... how does that affect tip wear over time? If one side of the diamond bears more pressure than the other? Is a tip that is nearly new on one side but with an obvious flat spot on the other still "good" or is it worn out?
Ray's posts will change how you see all of this. It's right there, for free... for everyone to see. No speculating, just clear photo evidence. Send him your stylus if you really want to know what yours looks like.