Im new to the site, and realize this is a somewhat irrevelant question, but anyways..... Ive noticed Amsoil is very popular on this site, they make great products, ive used them many times. In fact Amsoil is in the transmission, transfer case, and diffs in my tacoma as we speak. I also noticed Redline seems to be popular. I dont see too many posts discussing Royal Purple. I compare the three because they're usually regarded as the most "premium" brands, and the "real" synthetics. Also the most expensive Now, Id never heard of Schaeffers before i started poking around here, and realize its products are blends, but how does it stack up against the other three?