So in practice I have been using these for the usual stuff, sport climbing and wall stuff mainly but have also dabbled with the in my work to watch learners on rope access courses. They work great, Iv not had neck problems as such but have had a good case of belayers neck now and then and I cant see that ever happening again with these, they fit great, I can watch a climber, belay and still have good peripheral vision. I certainly would never leave for the wall or sport route again without them, they are definitely part of my kit now.
They get my vote and I have already recommended them to one of our regular customers who has a neck injury and up until now had given up belaying! He gave them a spin and belayed just fine! Other instructors I work with gave them the thumbs up too! What are you waiting for? http://www.yy-belayglasses.co.uk/