Do zipped ROMs take a performance hit?

When a ROM is zipped is there any benefit to it besides saving space? Does it impact anything for example like ROM scanning?

I don’t know about scanning, but it shouldn’t matter once it’s actually loaded, as it’s loaded into RAM at that point for most cores.

I’ve run into a issue earlier with a 7zip version of a rom where it was not allowing me to add or manual scan add the other roms that were zipped into it. Edit correction: when it was scanned it only added the first rom from that .7z file

Yeah, I don’t think support scanning merged/multi-ROM archives.

It does seem a bit faster when scanning non zipped but that might be just appearances. I’ve noticed with my current Lakka Version 3.2 that sega CHDs were taking forever, it was almost a minute just to scan.