I have no problem paying for super if it gives me some improvement. My other car runs nothing but super.. but it also makes 475 HP. Given what happend to gas prices in the last month or so I decided to try plus grade (89 octane) in my 05 3.0 X5 and I see no difference. Anyone just running regular out there? I'm considering giving it a try but I'm not sure how much advance the computer can take out... I don't want it to ever ping. I'm sure the computer is retarding the spark with plus a bit but I really can't seem to notice. Maybe he difference between my X and my sports car is just too dramatic for me to notice a 5-10% drop in the X performance. Any SUV feels slow to me even the V8s..it's just physics.. but I did not buy it to be a fast car. So if it is safe I would rather just use regular.