1st, I would only consider advanced stylus shapes, (except Mono, I keep an elliptical and microridge)
Ever since owning Shure's V15VxMR Beryllium Cantilever/Microridge Stylus way back when, I'm a fan of lighter/stiffer cantilevers, especially if it leads to lighter tracking force, which results in both longer stylus life which helps 'equalize' the higher cost over time, and reduced wear of lps that get played repeatedly. That Shure tracked at 1.0g.
Material/Rod/tapered/tube .... each yields published specs, compare them, divide the cost difference over ____ years, go for the best if you can afford it.
IMO, Boron is the best currently produced compromise, combined with a long lasting advanced stylus shape. I risked a used Sapphire Tube/Shibata successfully (my 1st used cartridge purchase/came with a test print out), I like it a lot, but do not hear obvious preferences compared to my AT33 boron/microlinear or my Jico Boron/SAS in my Shure V15Vxmr body.
Because the Sapphire seems 'equal/not better', I took risks lately with Vintage Beryllium, only available in used or NOS. I chose AT160ML
I subsequently learned that RUBY is actually a red colored SAPHHIRE, and BORON is closer to diamond's hardness than either.
The suspension must be designed for the combo, and advanced specs (channel balance/channel separation/tracking force) can only be achieved by successful implementation.
If you are not building a collection of cartridges, I would get alternate prices from Soundsmith, and compare the published specs, perhaps lightest tracking force the decider.
Happily VAS just confirmed all of my important stylus tips' condition as good and without uneven wear (most show uneven, thus anti-skate not correct) and cleaned deep into their suspension cavities which I only did once blindly.
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How will it get properly mounted/aligned/calibrated? (critical to both success and avoiding damage)
You, a friend, a pro, and who will periodically check everything? Never did it yourself? Current stylus playable but suspected worn? Now's a good time to buy any needed inexpensive tools and mess with the exiting one, practice, redo, redo, before you mount your new or rebuilt one.