Finally I tried one last time and exchanged the pink shift one for a SIXTH iPhone X...
I think I finally got the one I'm going to stick with...
It's quite similar to the previous blue shift one but even better, the shift is more subtle and more greenish than bluish.
It is not annoying in normal use.
To be honest, the previous one had an acceptable screen but I noticed it was consistently 2-3% slower than all other iPhones X (it was noticeable when launching apps at the same time, and confirmed by geekbench with a consistent result around 4100 vs 4250 for all other models)
The one I'm going to keep is the one on the right (6th one, no noticeable issue)...
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