We are very happy with our Spade - especially good on weedy bottoms and resets immediately if you swing when the tide or wind changes. We use a 10kg for our Vega, 2.5 tonnes empty. Anything 3.5 tonnes plus or over 30ft I would probably go up to 15kg, but the 10kg is fine for us and easy to handle.
There is probably a regional variation eg I sail in the Thames estuary and carry two CQRs, but if I was off to teh west coast of Scotland I would change one for a big Fisherman.
I used to work under a Fleet Manager who came from generations of Eyemouth fishermen (and was the finest seaman and man manager I have ever known) so I would be OK on the East Coast, maybe?
Were you involved in doing the survay, producing the statistics, if so is there a scatter graph of some sort showing the weight/size of anchors, chain, warp against the size of boat?
not sure of the relevance of what people have with what they would/should purchase now.
questions like - have you ever tried a new style of anchor even if happy with existing?
when was the last time you bought an new main anchor, and did your stem head fitting influence you ( I am sort of stuck with Bruce for example)