No, not that I've ever noticed. There might be some level of variation between units to roll off the assembly line so to speak, but nothing major. So you either picked up a used (and somewhat abused) one, or some third party top case that isn't up to the same quality standards. It's always the chance you take when doing this sort of thing on your own. You save some money, but sometimes the parts are lower quality or have been abused cosmetically.
Hi
I just perfomed a top case replacement on a macbook pro 13 inch. However I just realised the surface finish is a bit more rough compared to the previous top case which was smooth.
Is the aluminium surface on the top case meant to be rough and was there a change in the aluminium finish between different models(years)?
Thanks

Chowhound
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