My 8.5 Ezzy Cheetah has been feeling a bit weird, just noticed that 490 SDM Chinook 40% carbon has a slightly bent spiget so am suss about using it and about to go on a trip to Burrum.

I have an old, not sure how old, SDM NP CK 95% race 490 NP mast sitting here which says constant flex.
Looked ok upon rigging.
Worth a try?

Not sure if the older NP masts mean constant flex when it says constant curve.

Keen to try it with the much higher carbon content than the chinook to see what that feels like too.
40% Chinook 490 feels like a bit of a heavy beast. 95% NP feels much lighter rigging.

NP 490 and longer are constant curve. I think it will work. It's worth a try.

IT Will feel softer ,but it will work fine ,most NP mast are soft tops ,
have a good time at Burrum its great sailing there ,heres my cheetah rigged on a 100% NP mast
North,or duotone are a closer match for Ezzy's .

The Ezzy Cheetah specs say it needs a 490 IMCS 29. The Ezzy Hookipa 490 specs say it is IMCS 30.2.
Your NP 490 is IMCS 28.
A local here used to have NP race sails and masts before switching to Ezzy Cheetah sails, up to 9.5m. He used his NP masts. The sails did look a bit flat compared to mine with the Ezzy mast, but he went fast enough on them. He is 100kg as well. Quite often he would be on a size 2m more than what I used. So the top end didnt suffer, but maybe the bottom end did.
I know when I switched to Ezzy masts from Simmer SDM, the 8.5m Lion set a little fuller and felt to have a bit more low end power, but comparing the top speeds I found no real difference.
Same for all my Ezzy Lions/Cheetahs after switching from SDM Simmer to Ezzy RDM, the top speeds were similar.