Cup-N-cones have provided a gazillion miles of trouble free bicycling for squillions of cyclists.The trick with those on the Bromptun is to re-grease them properly when the bike is new. Grease seems to be charged for by the inch at the Brompton factory.
The bottom bracket is sealed though, should you feel a need for new-fangled apostasy.
I should add, that you might try to hire or borrow one for a day. I hated mine utterly, but 500,000 Londoners cannot be wrong. I should add, that you might try to hire or borrow one for a day. I hated mine utterly, but 500,000 Londoners cannot be wrong.
Sure cup and cone is fine, I packed grease in many of them when I was a teenage acolyte . However, I think the Tern makes nice use of standard bicycle components and as I'm polytheistic now I like to be able to mix and match. If I'm on a tour and have a mechanical problem it's good to be able to go into any bike shop and buy something from Shimano or SRAM and just install it. If commuting and trips on the Tube were all I was doing, then the Brompton's fold might make it the better choice, but I think I'll go with the greater versatility of the Tern and sacrifice a bit on the fold.