It's worth pointing out the PE hard product flown by the poster above on the A330 is not the same as the one the OP would experience on the A350 with CX.

CX uses the same seat bones on the A330 and B777, but a different design in both A350 variants. I haven't tried myself and CX may well still he worse, just saying I probably wouldn't bank on that to make a decision due to the hard product differences. Overall the CX A350 PEY seat seems to get favorable reviews here.