[shiroiushi]

>Of course, the floppy manufacturers warned that the cheaper single sided floppies had only been tested on the front side, and might have defects on the back. But I don't remember that ever being a real problem.

I remember someone telling me that the floppy manufacturers were obviously lying, because C=64 computers normally wrote on one side (back, I think), while Apple ][ series computers wrote on the other side, so the disks had to be tested on both sides anyway so they could be used in either computer.