My dislike for Framm filters is based solely on my own exp. with them. I thought the same thing you do initially, that the difference between the Fram and Mann oil filters is based on marketing and no hard scientific evidence, which is the reason one is still on my 760. However after 3000 miles with the Framm on the 760 and 240 I am convinced that the Mann is a superior filter. I recently switch the Framm filter off of my 240 to a Mann and noticed an instant and marked difference in start-up(starts easier quiter and the oil light now longer flickers for a second). What I did like about the Framm vs. Mann is that there are cheaper however now I can get the Mann filters for 4 dollars which is less than the Framm filters at WalMart.