On average, the OEM stator is likely to last longer than aftermarket or rewound stators but costs more. It's your choice. I you ride far from home, I'd go with an OEM replacement and a series R/R. If an outage wouldn't be a major difficulty, just replacing the stator with a cheap one may be considered. In any case, mounting a voltmeter so you'll see if the charging system fails so you can still ride to a safe place on battery power is a good idea.