Have used amsoil asl 5w-30 for the last 4 years on a vehicle with now over 150,000 miles on it. Change it once a year but now seriously considering only every 2 years since everytime the oil sample is analyzed at the end of the year, it looks brand new. My mpg also improved from 18 to nearly 21. I need 5 qts for $35 the filter another $15 for a total of $50 a year so it would be stupid and more costly for me to use any other synthetic.
To each their own but I recommended searching for it and giving it a try before forming any negative opinions about it. The only reason it's not in alot of retail stores is because amsoil won't give them a big enough discount for them to turn a profit and since you'll only need it once a year they wouldn't be able to move fast enough or afford to offer it for sale or clearance like they can everything else that is marked up so high to clear it off the shelves.
