We called OSX, not Apple OS. It do have live-dvd.
Also, EFI is better than BIOS for emergency, OSX is very rare virus. Linux do have virus too.
Extensible Firmware Interface - Wikipedia, the free encyclopedia
I bet you never see the EFI before. EFI is powerful diagnostic tool and easy to check all hardwares which it was good or bad. No download needs.
BIOS nope. That's all you had to download memtest86+, hd tunes, cpuz, GPU-Z, etc. It's waste of time.
Real reason why I like OSX over Linux for powerful app that I need as VRS,adium, arduino, seafoid, screenium, Pixelmator, etc which Linux dont have. I love Apple's design that it have longer battery life than most PC laptop with powerful cpu.
Apple MagSafe saved my life from our two huskies. You had no idea how many customers that they complained about their laptops fall down orlaptop power jack got broke. I had to apart everything to replace a new laptop power jack with soldering.
YouTube - Apple Magsafe Practical Test
PC laptop + power jack = Screw up.