I have followed this thread, as I did last year on compost. I used JAB year before last and from late last year to now have a wonderful selection of new weeds growing, which I am sure came from that batch. Last year I tried the garden centres own brand, less weeds but no real good results, so this year I am trying Levington's So far so good, but who knows.
I use mine for seedlings, potting on and for mulching, as well as digging into my wonderful (solid) clay soil along with grit, when I plant anything new, so do manage to get through a reasonable amount.
Sadly like Andy the Scientist I can't find New Horizon anywhere locally and to buy online usually means large quantities, then I have the problem of storage and OH is less than enthusiastic about piles of bags of compost everywhere!
yryinc, This U dud