have 20 years of service from my Sturmey archer Drum brake 7 speed freewheel rear hub.
I just took it out on the icy road yesterday, It's my winter shod bike with the studded tires
and it has just a 9mm solid axle..
have 2 QR Campag hub bikes with a 'wheels of boulder' replacement rear axle,
seems to be less brittle hard tempered than the original Campag ones were.
also OK for many years..