Which cantilever to choose for re-tip

Dear @jsbail : With out doubt you must go for the boron cantilever. At the ened the manufacturer designer decided that those cartridge models gone with boron cantilever.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

If you are a klutz most definitely Boron. Harder to break. Millercarbon, stick with your Koetsu and get off that "jitter" merry-go-round. Ledermann could never tell what these cartridges really sound like because they "jitter" too much. Imagine that, fixing all these jittery cartridges so they can "jitter" some more. Lets call up Lewis Carroll and have a tea party. 

I would leave it up to Peter.  Both times I sent him carts he felt the best way to go was to just replace the stylus on the original cantilever.  And yes, he used what appears to be a blob of glue to attach it, but the carts sounded absolutely great when I got them back.  I can't tell you whether they sounded identical to the original, but I was very happy with the sound.  

The best philosophy is to stay with the original cantilever material because the cartridge was designed and built with that choice in mind. So your answer is “boron”. This has nothing to do with one being “better” than the other. 

By the way, I am only quoting the advice of Jonathan Carr, who designs Lyra cartridges for a living.  He also pointed out that there is a significant difference in mass between boron and sapphire, which would have led the original designer to choose different materials for suspension and damping of boron vs sapphire, etc.