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?