Hi V8edd,
I see you are from Shropshire and a couple of guys use it from Telford. S Williams and R Yeomans to name a few.
It all depends upon the water quality and anions etc.. The honest truth from speaking to them they have not seen a good enough result as you can get in other areas. It only lasted a couple of weeks more than the product they have used.
I normally make a large drop in Telford and the local guys pick it up but not due there for a long time. You will find quite a few have used it in the Telford area. Worth asking aroundto get a true impression.