[Edit - I didn't notice who I was replying to.
@Luis H obviously knows far more than I about everything in at least the first two paragraphs. But I'll leave it here for general background.)
The basic poppet/seat design goes at least as far back as the original US Divers Conshelf and is still used by Aqua Lung. Voit took the existing part when they built the MR12 and Mares stuck with it after they took over Voit and used it for the 22 and later diaphragm firsts (except the tiny 42). I believe they are all interchangeable in a pinch, along with the Trident A244. Trident is the major aftermarket supplier of parts to scuba techs.
But I wouldn't mix and match if I didn't have to. The geometry of the orifice they seal against is slightly different between manufacturers and I assume that they optimize the seat/poppet face material for their orifice.
The Tri-Material 2k18 aka ACT is Mares' 4th iteration on this. I would assume they are getting better over time. The service interval has increased from replace every 1 year or 100 dives with the original part and first redesign called the PEBAX, to inspect at one year and if still good replace at 2 years with the original Tri-Material, to replace every 2 years with the current version.
All of these replacement intervals are overkill IMO unless you are trying to preserve a free parts warranty. As long as they lockup without creep and you don't have any reason to suspect problems, I wouldn't bother.
One last note. Mares did try a different design for both the poppet and volcano orifice for a few years. They called it SCS and added a V prefix to the first stages that used it, such as V16 and V32. Apparently lockup consistency was an issue for too many users so they went back to the standard setup.
This is what the SCS seat (orifice) and poppet look like:
The Ruby used the same seat, but the hemispherical part at the end of the poppet was replaced with a synthetic ruby.
You only need a new seat, the poppet and a different poppet spring to convert from SCS to the current configuration. Mares has a kit 46201386 with these parts.