0.1% will buy on impluse...
If you are one of those 0.1%, Im sorry...
No brand is better. ATI have more processing power but cost a lot more. While NVIDIA is cheaper but not as much processing power. Now one brand plays certain games than the other and vice versa.
I favor both Nvidia, one because its cheaper and two because Ive been using them for a while reliable, as well as ATI because of their processing power and ease to overclock and adjust the fan speed.
So research the card you want, compare, read buyer reviews. tomshardware.com is probably the best for video card comparisons and benchmarks.
Ive owned an:
NVIDIA GeForce FX5600, GeForce 7900GT, GeForce 9600GT
ATI Radeon 9000, Radeon HD 4870
None have failed to this day (well the 7900GT got a surge of power and was partially fried, but lasted for 6 months afterwards).