I'm in no way offended by your sig. I just said it was a snide remark and as such others can find offensive.
Anyways, as far as the actual drivers (the official ones) with stock settings and little to no tweaking, nvidia takes the price, after balancing out the faults on both driver sets. Running the bare skeleton of the driver is very useful and can cut down on resources being used, but most people prefer to just install things and run, and do little tweaking.
And ATI's Linux drivers do lag behind nvidia's. One of the main reasons I went over to the green side, since it was just ruining my Linux experience.