UEFI drive question?

Hi All,
Sorry but UEFI is all gobbledygook to me.
I have 4 internal hard drives:
500Gb SSD (C Drive)
2 x internal 1TB SATA drives, and I've kept my old 250Gb SSD which used to have my operating system on, inside my computer for backups.
I've disabled the 2 SATA drives, and my 250Gb SSD from the boot option, that's why you can't see them below.
Now, Iv'e just made a Macrium Reflect USB boot drive, and that's the only drive that is UEFI???
Should my main 500Gb SSD drive be UEFI as well???
Would it give me any performance improvements???
I haven't a clue!!!

UEFI does not give a general performance boost. It does, however, make boot times faster and allows the OS to utilize very large hard disks, and boot from partitions that are anywhere on the drive.

UEFI also provides some interesting functionality for other OS functions. I would make your systems UEFI compatible, because the day will come when you want to use a 4TB drive and you will find it will have problems with BIOS installs.

It isn't UEFI, it is EFI. EFI has nothing to do with large drive sizes. It is GPT disk formatting of that permits for drives larger than 4TB.

Making your boot EFI does require you to have a GPT formatted systems disk. But there are other compatibility considerations to be able to boot EFI, for instance your graphics card BIOS must support GOP/EFI or your system won't boot fully EFI.