Regarding the B&Q policy of not selling off ex display product:
I went through this a few years ago when trying to buy a wet n dry vac, reduced to £17:00..... I took it from under the racks and to the till, it was scanned and must have come up flagged somehow. Till girl rang the bell for a manager, who came along and explained that they cannot sell ex display electrical items because.....................and this is the bit to watch for...... because they cut the plugs off for display and thus cannot then sell because things are supposed to be sold with moulded plugs nowadays, so they would be breaking H&SE rules and compromising their own insurance with regards to consequent damages, litigation etc...
I looked at the "ex display" vac. it still had the plug on ! I pointed this out to the manager and he had to concur that there was no reason not to sell it to me....
When I asked what happened to all the ex display items I was told that they all get crushed......... What a waste of resources....
Anyway. hope this helps, just check if its got a plug on and if it has they cannot deny you a purchase.......