Is the mineral oil component of Schaeffer's Supreme 7000 group II or III? I've been a long time Mobil1 customer (5W-30, 7500 mile drain), but with the latest "improvements" and increased price, a change is in order. I drive a PT Cruiser 55 miles each way to work (appox. 3000 mi/month). 90%+ is at freeway speeds of 65-75 MPH (2800-3300 rpms). Would the Schaeffer's 7000 blend be a good choice for this application? My concerns are low/high temp perforamnce, oxidation, varnish/sludge, film strength, and it's ability to "hold-up" over the 7500 mile drain interval. Any comments/suggestions? Thanks!