We started selling the Bafang BBSO1B & BBSO2B mid drive conversion kits about 3 years ago. We have well over 2000 units out there now & selling more every day.One of the first bikes converted was my own Seven titanium road bike. Besides checking the motor mounting nut after a couple of months it hasn’t been touched since & after 12000kms is still going like new. There’s no sign of any water getting into the controller & all bearings are still fine with no sign of wear. So I’ve added some more grease & some Moreys oil additive which is wonderful stuff & will check it again in another 10000kms. These motors are simple, powerful & relible. What more do you need in an e bike?