*Last one was a B&D 550w impact drill...

Why? As a pro user, if you're buying a cheapie tool because you don't
use it much - at least buy something with a hope - like a new brand
that's trying to establish itself in the pro-tool foodchain. Or buy a
discounted/discontinued/ebay decent-brand model.

B&D spend all their money advertising their useless devices to the
gullible - not on manufacturing.

I politely told her about my contract being with B&Q and not B&D & the sale of goods act...

Good ploy - though sometimes the manufacturer support can be better
than the retailer support (though I find that unimaginable in B&D's
case - I would expect it to be as bad as their tools)