Now that I have a stash for my other two cars to last years, I now have only one car to buy for now, my wife's Cavalier. Her car has run on Mobil nearly all it's 70k, save for a few runs of PP and a quick run of QSAD for the first change. The drive train of this car is nearly flawless, as everything engine/trans/susp (needs just control arm brushings) is in great shape or been replaced. The body, on the other hand, is getting hammered thanks to 8 MI winters, as the rust is starting to show it's real ugly head.... Hence my little debate-should I stick with M1 until I unload the car (should still be a few years), or just run with a cheaper oil like the Super Syn or maybe QSUD? In honesty, I think there is not a real difference, but I think the cheap BITOGer in me is coming out. I kinda really want to try the Super Syn, but since this car only sees about 3 changes a year, spending an extra 12 bucks is not going to break me either. Quick stats: 70 city/30 highway...sees an decent amount of stop and go/short trips. Oil is been changed between 5-6.5k. (keep in mind lots of city) Thoughts? I'm tempted....but the gut says just stick with M1.