Question: Is pcie4.0 Reliable

[bman7500]

I'm considering building the lite version of the board (for a 2023 flow x13). I'm hoping to have pcie 4.0x8 speeds. Is pcie 4.0 compatibility hit or miss based on how good of a job the pcb company does manufacturing it? Or is it something I shouldn't be worrying about. Also, Is there a board parameter that helps with signal integrity that I could pay a little extra for, like thickening the outer or inner copper?

[osy]

I've found the cable is a big factor. I've bought 3 during testing and only 2 of them consistently gets 4.0 speeds while the 3rd seems to not work well.