Hello, I took delivery of my Brompton 3 months ago and have adapted it to suit me. I had a red Tannus tyre fitted on the rear wheel and find no problem with it. I note people on here talk about tyre drag....whatever that is? Does this refer to the tyre being solid? On the front I have a Marathon Plus. This is pumped to around 80 pounds. At this pressure there is no difference of hardness or 'drag' as people put it, between the tyres! also I notice the Marathon Plus is a bit dicey on drain edges just like the Tannus, so that shoots that argument in the foot....Maybe people just do what people do when something different comes on the market. I am considering having a Tannus on the rear tyre of my Dahon Vitesse to boot!