Grace Level ll

Don’t want to disappoint you @halcro , but none of the LEVEL II models have rounded plastic insert, your stylus has been replaced by the previous owner to the RS-8 (from previous F8, not LEVEL II), because this is the LEVEL II Ruby. As you can see the stylus replacement has rectangle shape, not rounded shape like your f8. Your box is from LEVEL II, your cartridge generator is also level II, but the stylus is not, i also have that rounder RS-8Ruby stylus and it’s from the previous generation to be correct. The original LEVEL II ruby stylus replacement is not red (and not rounded shape), it’s clear, the cantilever is red of course, but there is no "ruby" word in front. The stylus design you displayed belong to the F8 cartridge from the 70’s, but the LEVEL II Ruby invented in 1982. I know it’s too complicated, but this is how it is.

Grace LEVEL II cartridges are all comes with rectangle insert just like this.

But anyway, the question was about Sapphire cantilever, not Ruby.
The Ruby is well known since the F8 and F9, but the Sapphire is only for LEVEL II LC-OFC and i think it’s one of the rarest, it has white rectangle plastic insert with white sapphire cantilever. Here is the one i’m talking about. I also have the same rectangle Ruby for LEVEl II.

''Better than'' and  ''other than'' relations. I bought F-9 because
this one was considered to be better than F-8. But one can get
this ''level 2'' stylus for F-8 but not for F-9. I feel cheated for about
$150.
''The other than Raul expert reg. MM kinds''. Our ''new Raul ''
 comes from Russia. Not recognizable as such because of the 
name. Chakster is not an Russian name. Misha is. He remind 
me of my first experience with ''cart of the month''. But back then
 one could  practise this MM hobby for free. If one was fast and 
well informed. Even make some profit. Not so anymore . With
Misha we get similar prices as with MC's (grin).

Don’t want to disappoint you @halcro , but none of the LEVEL II models have rounded plastic insert, your stylus has been replaced by the previous owner to the RS-8 (from previous F8, not LEVEL II),

What difference do you think it could possibly make to the sound produced Chak.
I have the Level II Body, the Level II Generator, the Grace Ruby Cantilever and the Grace Line Contact Stylus (as opposed to the Super Oval of the REAL Level II).
According to your philosophy....the Line Contact should be an improvement over the Super Oval....? 🤔

I can find images for the Grace F-9 Ruby with BOTH square and rounded stylus assemblies.
HERE
HERE
HERE
HERE
If that is the case....why is it not possible that the Level II Ruby ALSO came with both square and rounded stylus assemblies?

I also have the LEVEL II Disco with BERYLLIUM CANTILEVER and boy....am I ever glad I don’t have it with the Boron cantilever as there is not a single boron-cantilevered cartridge that I listen to or is amongst my top 10 🤗
This LEVEL II Disco can be heard
HERE

It is very easy to explain @halcro
It’s all about chronology, depends on the year of production.
The best Grace cartridges made in the 80’s. not in the 70’s.

If you prefer to start with popular F9 series then all of them designed and sold with classic rounded shape plastic inserts, everyone familiar with this shape, look here. The F-9 is from the 70’s and much better than earlier F8 model. Many different diamonds made for F9 series, but the plastic insert is the same, just different color. When you will extract this type of stylus you will see a drop of glue on the back fixing the tension wire.

The next model was actually F12 (virtually unknown). For this model Shinagawa Musen also changed the shape of the plastic insert, it is no longer a rounded shape, it is a special shape, look here. It is interesting but if you will extract this stylus there is no more glue on the back. Same with F14 model released a bit later. This is the new shape of the F14 plastic insert, look at the back.

The styli for F12 and F14 are much better than anything for F9. They are better not because of the design of the plastic body, but mainly because they are made with top quality cantilevers, previously not available for any Grace F8 or F9, such as Beryllium, Boron, Sapphire and even the rarest impossible to find Ceramic.

This is one of the rarest Grace ever made, this model called "F14 Excellent", it’s black while all conventional F14 are gold. As you can see the stylus from F12 series is compatible with F14 (and with F9 too), so the owners of the F9 can ungrade their old rounded shape styli with new rectangular shape styli. This is the reason why you can find F9 with F14 styli on used marked.

But the signal generators were dramatically upgraded in F14 and LEVEL II series, the best generators are LC-OFC. For this reason upgrading just the stylus on previous F8 or F9 is not enough.

To completely upgrade F-9 we need at least F-12 or F-14 LC-OFC

To upgrade the very old F-8 series we need LEVEL II

Important:
1) F-8 and F-9 are not compatible
2) F12, F14 and LEVEL II are not compatible too

Here is the example of non compatible cartridges and styli: F-9e on the left and F8 with LEVEL II stylus on the right. 

The best cartridge from Grace are F14 and LEVEL II and there are many different styli to choose with different cantilevers and different diamonds.

I prefer LEVEL II to F14, but this is just my personal preferences, someone can prefer F14.

But the F8 and F9 series are old and not so special as the F12, F14 and LEVEL II because they never ever had the best cantilevers designed for them.

However it is possible to upgrade F8 cartridge body with better LineContact stylus from LEVEL II, here is one i had before.

I hope it will help to understand the story behind wonderful Grace cartridges.