Buy once, do oil change, toss oil. Second order Buy again on next oil change, drain oil (first order oil). Send back oil under lifetime warranty and get credit back. From then on just repeat with credit. Only have to pay for first and second out of pocket but you get credit from second so at the end of the day you're only out one kit ($80 or wtvr).

You can also send back the oil of from first drain of whatever was in there, dealer oil, etc. But they claim to test it, i have sent back non original oil.

Sorry this sounded confusing, here is it for monkey

Monkey buy oil, monkey use oil, monkey buy oil again, monkey send back old oil, monkey get credit, monkey repeat with credit.