Just ordered a B17 Narrow Imperial (cut out) from Chain Reaction. I have a couple saddles that are fine for 25 - 30 and bearable for 50. But, I'm going to test the mythology of leather and try to find a 'forever' saddle that I don't even think about for 50 miles.
I haven't had a leather saddle since I was a kid. I considered the Selle Anatomica X, but decided to try Brooks first.
I fully expect to be disappointed with the Brooks for at least the first 200 miles - will give it 500+ miles before deciding yes or no. If the Brooks is a 'no', then I will definitely try a Selle Anatomica X before throwing in the towel on leather saddles.
Reading saddle reviews is entertaining but irrelevant because saddle comfort is so rider-specific.