If I plan to replace cables OR housing on Campagnolo 10spd record, which would make better more accurate shifting.

without further info about your bike and amount of use... do both at the same time.

until you reach the bottom of the barrel, poorly wrapped cables, they are all about the same for "accuracy".

a housing type,quality and diameter will have more effect on "accuracy"

freshness and quality of a derailleur has a much greater effect... as does proper setup in the first place.

It is difficult to replace housing alone because the cable ends are usually chewed up from their anchor bolts making them hard to run into the new housing.

You can't go wrong with Campy and I have found Jagwire to be really good as well. Shimano cable and cable ends can be slightly larger but perhaps not in 10 speed.

Is there a reason you have to choose one or the other?

Brand name cables are all good. Shimano, Campagnolo, etc and many third party cable makers that have been around awhile. If you have Campy stuff, then use the cables Campy recommends for those particular shifters and brakes. If you have Shimano stuff, use Shimano's recommended cable for the particular shifter or brake you have. If you just don't trust trust them or think the difference in price is going to make you rich, then use whatever third party cable you like such as Jagwire.

You can sometimes get away with changing just the cable... if it's proper for the housing you have. But don't try to just replace the housings without also replacing the inner cable.

Be certain you understand how to adjust the components, cut the housing and other stuff you'll have to do. Shimano, Campy, SRAM all have their installation and adjustment procedures online. Some are a little harder to find.

why are you limited to one or the other? If you’re setting to system initially, cables and housing to get the routing and housing length dialed in. I use Jagwire Link segmented Al housing and whatever the best Jagwire cable is available. I replace the cables about annually - I can thread new cables through without disturbing the housing - I might replace the occasional corroded* segments when I’m replacing bar tape.
I use these cables with Campag 10- and 12sp drivetrains - shifting is spot on.
*the anodizing wears away where the housing contacts the titanium frame and the Al oxidizes

You want to always replace both unless for some reason the cable is damaged on a new bit of housing. Replace old cables and housing together, along with your sweat soaked bar tape and you will be much happier. I recommend Jagwire Elite Link or Pro Housing kits but being Campy you will either need new cables for those kits or just get the Campagnolo kits that have everything. Do not cheap out and try and only replace bits and pieces it is more expensive and causes more wear and other issues down the road. People who do piecemeal work pay extra for less and I never recommend that especially if someone is on a budget.

Plus, there is no point in replacing the housing without throwing new cables in there as well.

Kinda. If I had to guess how much the friction of shifting affects steel vs plastic, I would keep the cables if I could.

It isn't about the brand as much as replacing cables and housing when they become worn, corroded, or damaged. And then doing it right--paying attention to cable routing, seating the ferrules, and not damaging the cable as you're installing it.

Jagwire

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