I am happy with Selle SMP TRK on the Brompton - more comfortable than the original, while rigid enough to allow for maneuvering the bike while grabbing the saddle. Leather saddles may be good for fair weather riding (please no shower cap suggestions), but one downpour can finish the saddle. Cambium has big rivets for show which should be a no-no if trying to ride in winter weather - a layer of cloth is not really enough to protect you from the exposed metal - again might be fine for warmer times.