Yep, I can tell the difference between auto-inject and manual-inject, and that's a good point you make about the manual eject location. I believe that these are all 1.44 MB drives; I have no reason to believe that they're 800k and I know they're not 400k because there are 2 heads.

Even after thorough cleaning and lubricating, the drives still don't work. I have attempted cleaning the heads directly with alcohol with no better results. I've fixed drives before with this method, but I have a few that just don't seem to work for some reason. It seems that I have about a 50% failure rate with floppy drives in Macs I get, and I can fix about half of them, so I'm stuck with 25% bad drives... This seems kind of like a high failure rate, so I thought I'd ask if anyone has any ideas.