Howdy friends

Just got my Brompton today, loving the cycling quality, I cycled for 5 miles on it. It felt soo good

However, my bum hurts so I was thinking of going for something like this (without child seat of course, I'm talking main Rider saddle):



I'm not sure what Saddle model that one is, but I think it is the Brooks B66. Would the B66 fit on the Brompton ? Also since no dealers near me have or sell the Brooks B66, does anyone know how comfortable it is ... etc

Thank You.