My Sturmey Archer XL drum dyno has near 19,000 miles now. At 17,000 it got hungry and ate 4 bearings. The crumbs were all stuck on the magnet. ha. Wasn't too hard to put in another $7 part, needed to re solder the wire. This was after a tour with 300 lbs total. So the fork got overwhelmed and broke/ fixed 3 times. Brake is still good.

But I did have to make a 33.5 mm wrench to open it.