I prewash by hand with either All Free and OxiClean with warm water or use a MF cleaner like Pinnacle, MicroRestore or the DP to remove as much chemical as possible before using the washing machine. Why??? The grey rubber seals are lightly stained from not cleaning them well enough before washing.
I normally use the MF cleaner in the washing machine and use white vinegar in the rinse cycle. Dry using the permanent press cycle in the dryer without dryer sheets. Do not mix cotton and MF towels when washing!
I find that OxiClean and the All Free works better for removing brake dust stains from MF than the MF cleaners as a prewash. I really don't think that it matters which "free" detergent you choose such as All, Tide, Cheer or other.
APC+ also helps remove some compounds and stains that the MF cleaners struggle with as a precleaner. APC+ seems to help get waxes out of pads and towels. Sealants seem to give me the most cleaning trouble from a pad and towel standpoint.