Practicability considerations:
Signal Strength, related amplification factors
I also use only MM; higher output a choice factor, I prefer at least 3.5mV.
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Calibration Skills (and related tools)
Skills and tools for many alignments/calibrations are VERY important for ANY TT, ANY Arm, ANY Cartridge. Expensive or Basic. A bargain setup can beat a very costly system depending on calibrations. LP can beat CD, beat streaming, ... ONLY if properly setup!
Owner skills, or access to a professional for proper setup is important.
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Stylus Shape, Cantilever Material, Replacement
Think stylus shape, cantilever material, and cost/availability of replacement stylus now when choosing a cartridge.
highly respected source of replacement stylus
https://www.jico-stylus.com/
I prefer either Shibata or SAS stylus shape. I avoid the most brittle cantilever, thus I bought a replacement stylus: SAS stylus tip with Boron cantilever from Jico.
https://www.jico-stylus.com/product/vn5xmr-hg-sas-b/
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Cleaning Skills
Using advanced stylus shapes
with more contact surface in the grooves makes cleaning even more important. Clean Stylus is important. People who experience lots of disruptive static most often lack the proper cleaning skills. I recently improved my cleaning skills, and am enjoying my used LPs with SAS tip essentially static free.
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Elliptical Stylus is Less Costly
Example: Shure m97xe.
now discontinued (Shure stopped making cartridges). I used this quite happily for years. Jico makes a replacement stylus for it:
https://www.jico-stylus.com/product/n97xe-sas-b/comment-page-6/
Find one? Find a body and put a new Jico SAS stylus in it? (body you can return).
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Brushes
I like Shure brushes (and the sound of their cartridges).
Damped to steady LP irregularities, anti-static, and gathers small particles before the stylus gets to the grooves. Other brush arrangements exist.
Shure (others) with integral brushes can be used with the brush down in use, or pivoted up off the LP, Shure factory damped brushes, when down in use 'push up' 0.5g; so i.e. for 1.25g tracking force, using brush, set at 1.75 tracking, and anti-skate to match the 'effective 1.25 TF.
If set, and changing to brush up out of use, re calibrate TF to 1.25, double check anti-skate which was set for 1.25 already.
Jico wrote me that their replacement brushes are NOT damped, just a brush, so the upward force is different, a bit of guess work involved.
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Protection of Stylus
Check out the method/ease of stylus protection during detailed arm/cartridge/stylus calibrations.
Shure flip up/down brushes, Jico replacement stylus with flip up/down brush, and Audio Technica slip on protective cover are all easy.
My Grado Mono cartridge (love it's sound): it's small snap on plastic cover is ok for shipping, but lousy for protection when calibrating.
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USED
I would consider buying a used cartridge body, from a highly regarded source, only if returns accepted.
I would plan on the cost of a replacement stylus in cost calculations.
Used Stylus, separate or comes in used cartridge body you want: that's risky, might get lucky, but