Earlier quoted context omitted.
That there even worse alternatives isn't helping. Avoid third party binary modules. Sure, they might work right now but you'll have no guarantees it'll work in the future. You also risk interactions with other subsystems (sleep etc.). It would be like Windows, where your printer might prevent you from upgrading your operating system. If you intend to run Linux on the thing, buy things that Linux supports out of the b…
While your theoretical point of view is solid, reality kind of disagrees with it. The binary blob provided by Nvidia have been quite reliable across the years (and I think they've been available for more than 10 years) while the open source ATI/AMD drivers have frequently failed to deliver.
In my experience, the open-source radeon drivers are significantly more stable. Fglrx was a stinking pile of crap that has officially been abandoned - the whole driver team has switched to the open-source drivers, now.