Ya I was researching the GXP a lot before I bought it and new this was an issue, luckily my car doesn't burn that much right now. I threw a code for a cylinder 7 misfire and wanted to changed all of them because I am not sure how well taken care of it was before I got it. Now it gets the best of everythingI put some NGK IX in it, and the difference is night and day. Just on the throttle response alone, it moves when you give it some gas. I also put some Fuel System cleaner in my tank when I refilled up so hopefully that'll help freshen everything up. It already has MSD wiring, K&N cold air intake, SLP cat-back exhaust system, transmission cooler, and just slapped some new rubber on her too. In love with this car
As far as the spark plug, it looks to me like a combo of just normal where it some of the oil burned, not much, but not the same as the others. It's not something I am worried about though.