Linux compatibility and security dangers of UEFI "BIOS" in Asus N550JV

[otropogo]

Have just acquired an Asus N550JV, and was unpleasantly made familiar for the first time with the UEFI "BIOS". The laptop comes with a generic user "manual" that doesn't even include a spec sheet (and you have to download it from the Asus site), and is totally inadequate in its instructions for external booting. I have yet to find a real manual for either the hardware or the firmware.

I sought help from the retailer's (Staples Canada) local technicians, and was told categorically that it is IMPOSSIBLE to boot Linux on this machine, externally or internally, unless one first totally wiped the hard drive and thereby eliminated any possiblity of using any version of Windows on the machine thereafter.

Of course, a few minutes with a search engine and a few more minutes tinkering with the UEFI menu proved this to be total nonsense, and after the proper adjustments, I was able to boot the machine from a Knoppix 7.2 usbflash install. However, my reading on UEFI, particularly the Wikipedia article, together with the lack of technical support from either the retailer or the manufacturer, makes me seriously wonder whether I should return this machine for refund, a decision I'll have to make within little more than a week.

Of particular concern is the UEFI "BIOS". While one of the store salesmen was trying to figure out how to boot externally on a couple of the store demo machines, using several of my bootable media, I saw that the critical menu entry - the toggle to disable secure boot - without which it's impossible to boot from external media - was missing on an Acer laptop with UEFI.

The BIOS on my machine has already been revised twice (mine is v2.04, the latest listed online is v206), and I'm worried that these revisions might remove my external boot capability. Is it possible to revert to an earlier UEFI BIOS after upgrading, or is it a one-way trip?

Other, more subtle, obstacles to the use of Linux or older OSs are suggested as possibly being concealed in machines designed for UEFI. I'm not knowledgeable enough to assess these threats, and would welcome any comments on their seriousness?

Frankly, I don't trust Microsoft or Red Hat (which according to Wikipedia, has jumped on the UEFI bandwagon with gusto), and am not willing to give up access to other or older OSs than those two offer currently. OTOH, I have no opportunity to test or even examine top end laptops in my remote location. The one in question was one of the first three Haswell cpu machines offered in my vicinity (ie. within 120Km), and even then there was no demo machine to view, so I ordered it sight unseen on the basis of very skimpy information.

I've found only one in-depth review of it online, albeit from July and of a pre-production model, which gives it high marks, but doesn't address the compatibility issues posed by UEFI at all.