Wallingford's gives a 6 month trial on the Brooks. Nashbar gives complete satisfaction, with a refund if returned within 12 months. Performance also gives money back within 12 months, with few questions asked. (I returned some Shimano pedals, and the questions revolved around whether I gave them a fair trial - no pressure to keep them.)

Brooks has a saddle with springs that may be great for you. I'm 230 or so on the bike, so a lot less than you, but my Brooks imperial is breaking in nicely. I suspect that the leather breaks in more easily the heavier you are.

They're expensive, though. Financially, the problem occurs when the Brooks does work well.