6) They are leather, so wet tours might be a problem,
7) Many of the popular models have limited set-back, particularly true with the Pro, so look at your current set up and if saddle is slammed all the way back you may have fit problems with a Brooks,
8) Break-in varies leather to leather, I have a honey that took a year - and some tenderizing with a baseball bat,
9) A very few of the models, B18, B66, B72 for example, use the vintage double rail two bolt clamp and not the modern single bolt seatpost. If you attempt to use one of these with a more modern seatpost you have to buy an adapter,
10) Your saddle will be attractive to thieves, (easy sale on eBay),