Actually I didn't see anything about licensed spectrum on the site, but of course that helps with backhaul and high-end subscribers. For many years we really didn't see any interference issues with P2P links @5GHz but that has changed recently. We have been deploying dishes with shrouds to cut down on sidelobe gain.
My experience has been that interference is as much a problem at the CPE side (and much harder to diagnose there) than at the AP. I've also noticed that with Ubiquity/Mikrotik-grade radios in the 5GHz spectrum you can easily get interference from your own co-located radios at the same site, using different channels (because they are not so good about suppressing out-of-band radiation).