I've got carbon reeds in my NSR, which has done a couple of seasons racing, a bunch of trackdays and a few thousand road miles. No problems so far.

I've also not heard of someone destroying their engine due to reed failure (until the KTM mentioned above!).

All these things are down to an individual to assess the risk and what they're comfortable with.
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball