Upgrading Brakes and Shifter, need to change cables?

[pragrick]

Hi all, some advice needed. I am upgrading my brakes, shifter and derailer. I'm going from Shimano MT520 4-piston hydraulic disc to XTR and SRAM NX set up to XTR. Can I use the same cables or do I need to use new ones that come with the gear? Or should I use something else? Bike is new. I see this (below) on Shimano's website, is there really a performance difference? Thanks

 

[Mteam]

Technically you can use the old cable, but you may find that when you take it out of the old derailuer to thread it into the new shifter it frays (because you need to remove the crimped end off the cable) which makes it hard to reuse

A new cable is only a few quid you may as well replace it.

 

[R120]

Just keep the cable outer for the shifter, and replace the inner - if you are buying a full shimano groupset, or the shifter individually, it should come with a new cable preinstalled anyway