There is no easy answer to that question. Both oils show great results. Redline is a company that has geared itself towards the racing crowd, while Amsoil gears itself for the longer drain crowd. So that could play a factor in your decision. To truly get the answer to this question you'll need to run both oils in the same car for a few intervals and see how the oil analysis results turn out. I bet it will be too close to get a true answer though.