Just over 22,100 miles (as of this posting). Still running the original stator. Still getting strong readings from the voltmeter monitoring the bike's charging system.
To make the stator last as long as possible, do whatever you reasonably can to keep the stator clean, and minimize the heat it has to put up with. Thus, you can do this with the following:
1) When possible and practical, avoid riding the bike in stop and go traffic, especially in hot weather.
2) Keep clean oil in the engine, and keep the oil level topped off (but don't put too much in there, either).
3) Keep the bike's electrical connections clean (i.e., using dielectric grease as appropriate) and tight--don't allow them to corrode. This is especially true with the battery connections and all major ground wires--and also the 6-pin connector for the regulator/rectifier. Periodically inspect these to make sure they have adequate dielectric grease on/in them, and they are tight. An excellent "primer" on this topic can be found at the beginning of the electrical system chapter in the Clymer repair manual for this bike.
4) Relocate the bike's regulator/rectifier, as recommended by other relevant threads in this forum. While there is no definitive proof that this keeps stators from failing, it usually keeps the regulator/rectifier cooler than the factory's chosen location (underneath the battery box). If the regulator/rectifier runs cooler, it stands to reason that the stator will be happier, too.
5) Keep moisture off the bike when it's not being ridden. Either park it in a climate-controlled garage, or put it in some other shelter where it's totally enclosed from the elements. At a minimum, if it's parked outside in the open, buy a high-quality cover and use it when the bike's pipes cool off after a ride.
Practicing the above will allow the stator and the regulator/rectifier to last longer.
In short, be good to your "baby" and your "baby" will be good back to you....