I use the narrow Velo-Orange leather saddle model 106 on my Brompton S1. I have used it in 100 degree heat and in more moderate temps for 2-3 hours at a time without any problems in terms of saddle sores, numbdick or any other issues. It seems more stoutly made than my B-17 narrow as the leather is bonded to some kind of mesh and the saddle is joined underneath in the middle to prevent splaying. the rails are a little longer than a Brooks so you get a bit more fore and aft choice. Mine is the honey color which I think looks nice with Ergon cork grips. I like the saddle bag loops on both the Brooks and the Velo-Orange saddles. The Velos are 110.00 right now on VO although they have 20 % off until 12/14.