I moved up to the Adrenaline 13 from the 12 a month ago and have had agonising foot pain and had to take a lot of time out. On checking the design, Brooks have added a large section of rigid fabric on the inside of the arch which extends further down towards the forefoot. This is causing my metatarsals to be squeezed together, and from the pain they must be rubbing together too. I'm returning them to Amazon and will try a size larger or, if that doesn't work, switch brands.
I'm biased as I run with Ealing Eagles but this is a clip of EHM from their 2012 photo reel, which shows the feel of the course really well. I think they're planning to extend the course to include another of the parks this year.