All the comments made to date have merit. As I have mentioned before just because the study was funded by Amsoil does not invalidate it. Every oil manufacturer in the study can contest the results if they feel they are significantly off. Every manufacturer, whether it be P&G, Loreal, Unilever, Ford, Chevy etc. funds studies and if the results look good for them they market the heck out of it. If the results do not look good they just don't say anything about it. Amsoil is no different. However, the distribution channels Amsoil uses would in my opinion add cost. Lizards comments mirror my own in that under real world riding conditions I bet any of the top oils are going to be comparable so pick the one that is the most convenient to purchase. Price is not that relevant in the grand scheme of things. $4-$5 per oil change is not much given that is about 2 gallons of gas. It has been my experience that instruments can often quantify differences that the consumer, or their machine, can not.