[cctalk] IBM 5120/5110-3 casual notes / 8" disks question

I finally got an IBM 5120 earlier this month, to complement the 5100 and 5110 that I already have. It had a few issues, but I did manage to get it to "boot" to BASIC. I put together a few notes about it here. Nothing too exciting, but two things I've learned: (1) the 5120 does actually still have the video REVERSE feature. (2) the 5120 has both an external (red power switch) and internal power switch (internal one is at rear below disk drives). Notes here: https://voidstar.blog/ibm-5120-aka-ibm-5110-3/ IBM 5120 (aka IBM 5110-3) — voidstar <https://voidstar.blog/ibm-5120-aka-ibm-5110-3/> My only question is: how "universal" are 8" disk? This 5120 only came with a single IBM 8" Diagnostics disk. It looks to be in fine condition, but I've no idea about the data. So far I haven't been able to read it - it's probably more hardware/drive issues, I'm still investigating. But I'm wondering if I had other 8" disks (3M SS/SD), should I be able to format/MARK them? I've used old tape decks and 5.25" drives - but 8" drives is all new territory for me. Also, I'll be talking about the 5100/5110 at VCF next Sunday on the 25th of this month, June.