i know this is a can of worms and i have been using Mobil 1 since 1988 and have been satisfied with it. now my question Mobil 1 verse castrol edge castrol claims that their edge out perform Mobil 1 by 8 times or some thing like that.i read a little on here last night at 1:30am (stupid me)for being up that late. one guy post a letter from the API about Mobil 1 meeting all the api specs but castrol edge claims that the edge will reduce wear 8 times better than Mobil 1. if castrol edge is 8 times better then i want to use it but if its not 8 times better i will keep using Mobil 1. the cost of oil is not a deal breaker for me i just want the best oil that i can get for my cars we drive our cars a long time. i drive a 2000 vw beetle tdi & use Mobil 1 5w40 turbo truck & SUV oil in it and the wife has a 2003 VW beetle with a 2.0 gas engine that gets Mobil 1 0w40. so whats the best oil of the two i never did fine the answer that i was looking for last night.