Depends. In theory it is fine, in practice it is a big ball of mud.

I'm starting to like Apple's approach more. It allows to have multiple OSes installed and each to have different level of trust. In UEFI, the equivalent would be that you could have Secure-core like security for one installed instance, 3rd party UEFI-enabled Secure Boot for another and no Secure Boot for yet another installed OS. Unfortunately, in UEFI it is all-or-nothing instead.

Right, it was secured(from a foreclosure auction). My collection is fairly modest, and getting more and more dated every day, so it was a bit of a curveball to run into something with not the usual BIOS. I think i sent it to GoodWill.