If weight is the OP's concern, get ride of the bike and forget the Brooks. If enjoying the ride is the goal, keep the Raleigh and get the Brooks. Personally, I love almost every Brooks saddle I have ever tried, with a single exception, the Brooks B15 which was, for me, the saddle from Hades.

In fact, I have had a Brooks B17 honey kicking around for about three years. The saddle is almost brand new and looks just great on my recently built up Motobécane Grand Jubileé. No picutes of that yet and it looks as though I will be hanging onto my Motobé for a while. I love that bicycle!