I'm looking at doing an oil change here in February (I like to change the oil in Spring and Fall, and sooner if necessary), and out of curiousity I did a little rooting around the interweb and found this
It's a rather comprehensive comparison of the top brands of oil, including: Particle Wear (ie. how much wear on the engine there is at a set intervals), Top Horsepower (Self explanitory), and vicosity loss.
Needless to say, I find it very useful, and thought I'd make a little contribution to help everyone out a bit.
aahhhh....normal driving.....Who defines that? lol
I found that having all the information about the different oils provided allows a person to choose the best oil according to their preference, though, Mobil 1 0-w40 seems best for horsepower increase, and Royal Purple for engine wear. Personally, I think I'll be running Mobile 1 0-w40 just for the additional power. After all, the engine wear is fairly average, which is fine considering that engines wear out (fact of life), and eventually I'll be moving to a newer vehicle, at which point I'll most likely either trade in my G6, or keep it and just run Royal Purple for the sake of maintaining it well (which I hope the rest of you feel similarly about), but until then, the bottom line is, the G6 is performance, and we like more power, and, in my opinion, the 0-w40 from Mobil 1 provides the best increase.