While I share your admiration for those 3 cartridges, and I own them all
You own them all ? You like them @lewm
Thousands people own them and use them too, and feedbacks all over the internet, except maybe SONY XL-50 (a very nice cartridge).
Would be nice to read your comment about SONY XL-50 MM is you have it.
Grace is probably the most popular, honestly i have never seen a bad sample of Grace, suspension always fine, i owned F-9E, F-9U, F-9F, various F14 models too and so on ... up to LEVEL II. As you know i like Grace and collect them. If you think the suspension is dried out a bit, then maybe a compliance is a bit lower now, but originally it is very high compliance. But i never seen a softened suspension on any Grace samples out of many samples. And you’re the one who use SoundSmith Grace, so there is a person who even produce NEW styli for Grace. Just look HERE>
Brand new styli (not a retip of the old one) available from SoundSmith and he made them. One of the reason i can recommend Grace for a novice.
Personally i'm ready to buy as many original Grace styli as i can before they are gone. It was such a great company and they gave their customers so many options (so many different styli/cantilevers, we discussed it before).
Old Pickering is also extremely popular cartridges, on another forum anyone can find a "fan club" of Pickering/Stanton where people share knowledge. Why i never seen any sample with bad suspension? I think the design is just right, so using them in 21st century is not a problem. About service: Expert Stylus & Cartridge Co in UK specialized in Stanton/Pickering repair, their stylus Paratrace is the closest to Stereohedron. Anyone can contact them by email ( info at expertstylus.co.uk ), my communication with them was very nice. I think our friend @nandric retipped some of his best LOMC with them.
There is no risk to invest in cartridges if you know where to buy them, or your formula can be applied to anything vintage (tubes, turntables, speakers). Why people buying vintage gear in 21st century ? Because in many cases it’s better and often cheaper. And it’s cool.
P.S. New MM cartridges like Nagaoka and AT are always in the shops, they can wait... nothing special