I have the same mill that over time exhibited the roller turning problem (the O-ring lasted about 30 seconds). Disassembling, cleaning and relubricating the rollers fixed the issue for me.
I dust it off after each use, but it is not meticulously clean and a lot of gunk builds up over time.
It has worked well for me for about 12 years now and needs cleaning every couple of years (I grind through about 240 pounds of grain per year on average).
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