I have been using my stash of NAPA Synthetic 5w20 and have had not one complaint using an OCI of 6-7K. I have noticed that the oil stays clearer looking than when I use MOBIL 1 and it been on sale on a regular every other month basis. I have always used Mobil 1 or Valvoline Syn Power on my vehicles and have gotten up to the high 200 k out of all my cars. In order to save a few bucks im going to be an avid NAPA synthetic guy for awhile.