Which needle for sony xl-45 cart, NOS or Jico sas?

There is one significant advantage the SAS has - it's new. No time for the rubber to deteriorate.

The original Sony composite aluminium/carbon fibre cantilever is a key ingredient in achieving that neutrality. With the SAS the sapphire cantilever would be much closer in sound to the original than the Boron.

With regards to the stylus shape - the SAS is probably better than the original.

On the Sony XL55mkII Sony moved to using a micro ridge profile.

You'd better pay the "buy it now" price of 45,000 yen ($313) for the Sony ND45X stylus before the auction ends in four days! Otherwise someone else is liable to scoop it up! Apparently this stylus is pretty rare!

Apparently this stylus is pretty rare!

Apparently so, but not as rare as a NOS stylus collapsing after a short time due to deterioration after 20-30 years storage.

Still, you could buy it and mount it on the wall as a piece of art.

I vote for new Jico SAS on boron. Fresh suspension. I got one for my Shure V15Vx body, sounds wonderful.

Yours has no stylus. Just to note:, Shure, perhaps Sony made ’alternate’ interchangeable stylus, you could put elliptical, line contact, some even allowed stylus for 78’s. into the same body

i.e. perhaps you don’t really know what is in a used cartridge you buy.