"First, yes, there has been a changeover with the LP S. Benz has gone to a micro-ridge stylus(thus the "MR"). Second, so far I think the Benz LP-S MR is one of the two or three best cartridges I've had in my system. It is outstanding." - Jonathan Valin
The Benz Ruby-Z is the current latest and greatest in the Benz Ruby line that all started with, well, the original Ruby. Like a great movie, next came the Ruby 2,..the Ruby 3, EXCEPT, that the cartridges kept getting better! Pearl Audio founder owned a Benz Ruby 2 as his very first high end cartridge and followed it up with, well, other Ruby 2, then later a Ruby ZH because he had a lower gain tube phono stage to keep happy.
The Ruby's have always been and always will be about superlative bass weight combined with reference class resolution. The sound is driven from the bass upward with tremendous power, finesse and refinement while tracking true four-wheel drive territory variations in the vinyl, aka high dynamic recording. The big Benz's are absolutely unflappable. If they were cars, take one guess as too which brand they would be.
Compared to he Benz LP-S, the Ruby Z cedes a little bit of bass weight and power, but gives back in versatility. There are instances where you want to put a Benz LP-S on a table but the tonearm cannot handle a 16g cartridge. It's not just a matter of the tonearm weight being heavier, it's the stoutness and hardness of the bearings and the tonearm's structural strength. It's same reason you cannot put 32" tires on Benz SLC automobile, which has very high quality suspension components, but you're fine on a G-Wagon. The Ruby Z comes in at a slightly heavy 10.7g, so it's compatible with most high end tonearms.
The internal Ruby Z motor has an (upgraded) classic Ruby non-ferrous square plate/Neodymium generator and comes in two versions: .35 mV and .7 mV which gives even further versatility. You cannot run a .35 mV cartridge, at a high level of performance without having a phono stage that can cleanly amplify in the ~65 dB range. This means that many tube phono stages, un-specifically the ones that don't cost more than a used '09 up Boxster, will have audible background noise. The .7 mV Ruby ZH has heavier windings than the standard .35mv Ruby Z, ,so you are giving up some fleetness and resolution but in return you can use superb mid-gain phono stages such as the Audio Research PH9 and many of the upper shelf preamp internal phono stages. A Ruby ZH is also less susceptible to RF noise which is a common issue in denser urban areas or areas near a radio tower, Portland Oregon being a poignant example.
Like its big LP-S brother, the Benz Ruby Z has a micro-ridge stylus. The body is made of Zebra wood which is similar to the sonics of Ebony but a little bit warmer and woody harmonic sounding.