Polaris RZR 900/1000 & Sportsman
The newer Polaris RZR 900 & 1000 XP models are developing a reputation for regulator failures. The regulator is mounted in a poor location from the factory on these models, near the engine and open to the wheel well were it can easily be covered in mud and dirt, significantly impacting it's cooling ability. A MOSFET regulator is an essential upgrade on these vehicles because they run much cooler and will stand up to the limited cooling.
A regulator failure can cause your stator to fail, doubling the expenses to replace both parts. By switching on a more reliable Mosfet regulator, you can save your stator for failure.