Hi Dave if you add your engine details under your avatar on the left it saves people having to look it up.
Haven't heard of many of these being replaced, and we've had a few diesels in the family. My own car has done over 403k miles and still on the original Flexi and catalyst.
If I did need to do the job I'd replace the Flexi and catalyst complete, but only as I have a spare new one that came with a scrapper I bought a few years ago.
So not much help but you get a free bump.
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