Thanks for the comments, I've updated a couple of the pro's and con's 
Interesting that clay can have such a pronounced effect, I have very loam'y/silt'y free draining soil so I suppose that will have a less pronounced effect on the height of the soil. I think I am going to go for 'A' as I am concerned that I will damage the hardscaping and/or the reel is all slate so will show damage quite substantially.
Interesting that clay can have such a pronounced effect, I have very loam'y/silt'y free draining soil so I suppose that will have a less pronounced effect on the height of the soil. I think I am going to go for 'A' as I am concerned that I will damage the hardscaping and/or the reel is all slate so will show damage quite substantially.