XYplorer Beta Club

Is safe overwrite slower and/or more intensive than a regular copy/move operation? My drives have been dropping out during large transfers, and while a lot of it probably has to do with Marvell's less than stellar SATA controller, I want to know if this may have anything to do with it as well.

I don't think so. It's still a normal copy operation, but with two additional delete and rename steps. Safe Overwrite simply copies the source file A as file C, deletes target file B, then simply renames file C to B.

Correct.