UEFI BIOS yes/no?

It doesn't really matter one way or the other, it's just that a UEFI BIOS is GUI (graphically) based instead of pure text based, like a normal, old school BIOS.

Personally, I LOVE the UEFI BIOS on my Asus P8Z68-V LE board. I will never buy a board that doesn't have a UEFI BIOS now (I'm thinking UEFI will eventually be the norm, anyway). It's just SO much nicer and easier to work with.

Traditional text shell BIOS is what you should be avoiding because it just goes to show that the motherboard manufacturer is not willing to keep up to date with technological advancements.

Wikipedia describes the technical differences but so far I can't see how the machine I'm building will see any real benefit. Plus seeking a USFI BIOS limits your choices significantly.

So far, in this post, you haven't specified any details about the new machine that you are building and I'm not a mind reader.

Unless you plan on buying a low-end or very old motherboard, most new mobos have UEFI BIOS regardless, so "limiting your choices significantly" isn't a very strong argument against it. Even this cheap ASRock AMD board has UEFI.

I don't recall asking for a critique of my component selection so your mind reading skills are not in play. I was hoping to hear from builders who had experience with this BIOS and could share the strong & weak points with me. If that's not you perhaps you should move on where others might appreciate your sarcasm.

It's your statement "I can't see how the machine I'm building will see any real benefit." and yet you don't specify anything that supports or refutes that statement.

If you're going to be using HDDs that have a capacity of more than 2TB each then you will need an EFI BIOS if you expect to be able to use the HDDs' full storage capacity.

I read about the 2TB limit on Wikipedia however it doesn't seem like a limitation I can't live with. Thanks for pointing it out though.

FWIW, I just read that Microsoft seems to want to use a feature called "secure boot" to prevent Linux from loading on machines with OEM W8.