Sony XL55 Pro

I recently acquired a Sony XL-55 Pro with intact cantilever but missing the stylus. I had hoped to retain the aluminum, beryllium, and carbon composite cantilever, but it seems that retipping it is not an option. So my choices are: Soundsmith (aluminum cantilever with nude elliptical, sapphire with line contact, ruby with line contact, ruby with "optimized contact," and boron with line contact); Andy's Needle Clinic (sapphire with linear contact or micro ridge); or any of the various offering from Garrott Bros. or Expert Stylus. My preference is to not send it overseas unless there is a clear advantage, so that leaves the options from Andy or Soundsmith. I have a Sony XL-44 with Soundsmith ruby cantilever with the basic line contact, and I am happy with it, and I suspect the "optimized" profile may be too persnickety for a integrated cartridge/headshell like the Sony. What advantage do you think the the boron upgrade offers, and conversely what do I give up by going with slightly cheaper sapphire option? And how do they compare to the linear contact of micro ridge needles the Needle Clinic offers?
Before you commit try this guy:

I ever started a thread about ''irreparable carts'' but, alas, got

hardly any response. The Sony's series XL carts belong to

this ''category''. Not only because the plastic body is glued

together and need to be ''cut'' to get access to its inside parts but

 the carts inside parts are  ''potted'' . Even according to Mori ,the

XL series designer,  are those carts irreparable. My XL 88 D

(D= diamond cantilever) is ruined by Axel's attempt to fix it.

This however does not mean that the stylus /cantilever can't

be changed . Those are reachable from outside. The ZYX carts

also have glued together bodies and problems with suspension.

To change the suspension one need to cut the ''covering

plate part'' and drill a hole on the left side to get access to the

fastening screw. I own the Airy 3-X which got new suspension

and stylus but with two ''holes'' in the body. This repair was possible because the inside parts are not ''potted''. However I fear that my Airy 3-X is unsaleable with its ''mutilated body''