I am about 400 miles into a brooks flyer and so far so good. it's not quite broken in so time will tell but I do notice that the springs very clearly make a difference. I am just waiting for that lap of luxury feel from the leather that so many have described...

If you google b17 vs brooks flyer a bunch of threads will come up that discuss the difference between the two. Some in those threads say that the springs only help on the big bumps and hypothesize that they would only benefit heavier riders but I haven't found this to be true (nor did others in those threads). Not only do the springs help with bigger bumps but they also dampen road vibration. I believe the springs make the flyer 10 ounces heavier than the b-17...