I have been using amsoil since 1974. The only problems i have heard about switching is when people switch on high mileage over 100-150k or more on vehicles they haven't cared about (using really cheap oil or never or rarely changing it. It seems that these engines are running on sludge or sludge is filling in the gaskets or the spaces in between the rings and the cylinder walls. Amsoil, being a super detergent, will clean out all the sludge, and these worn-out engines will start leaking oil, or using oil, or both. So given reasonable care for your engine, and changing oil regularly, you should have no problem.