Has anyone done the Farrow and Ball proper method for floor painting?

[LauriefairycakeeatsCupid]

I have painted floorboards white in other houses with success in a kind of shabby chic way but I have started to do them properly in my high traffic living room.

I have undercoated with Farrow and Ball undercoat - a silver metallic paint. Then topped with first coat of floor paint (need to paint second coat on according to instructions).

Any idea since I've done it properly how long it will last? Farrow and Ball say up to 5 years - I've had to repaint every year in the past when I've done it.

I have never done it but it does last better than any other method.A friend has done it on his stairs and it has looked good for years even after letting the house when he went travelling.

We did our stairs the proper way (and about 4 or 5 coats as it was up the sides with runner in the middle) and it looks fine 6 months on, though it does show up the dust something rotten!