I used 501 on a 2004 Ford Escape. You should have seen how much dirt it took out of the paint. I also used it on my wifes Kia Sedona 2 months ago and it still beads like crazy. The Ford also got the 105, but the Kia only got the 501.To be honest..501 will clean paint much better than 601...601 was made to clean off old waxes and sealants....501 will deep clean paint...it will remove oxidation thats how strong it is
Al