I think they are 30mm cranks that can be used on BSA frames with a BSA->30mm adapter from Rotor / Zipp etc.
Durability wise it would be no different to using any other external BB.
(I'm assuming the TCX BB is BSA threaded...?)
@Howard started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
I think they are 30mm cranks that can be used on BSA frames with a BSA->30mm adapter from Rotor / Zipp etc.
Durability wise it would be no different to using any other external BB.
(I'm assuming the TCX BB is BSA threaded...?)