I'm thinking about switching to this oil down the road when my Syntec stash runs out. It looks to be about $27/12qts. at Costco right now and hopefully can find a coupon/rebate also. I am one of the 3000 to 4000mi. OCI people so I figured I might as well go dino, and I've read that Supreme is Group II+ and/or Grp III. It sounds like this used to be a highly reguarded oil on this site. was that do to price, performance, or both back in the day? What are you thoughts on this possible switch (for a 99 GM 4.3).