I was brought up in the UK but I have spent much of my adult life in France, Belgium, the Netherlands and Luxembourg.
When I was 13 (so in 1963) we were told by our physics master that we would be the last intake of students that would have to study Imperial weights and measures alongside the metric system. In future, he said, only metric units would be included in the course material. Bearing in mind that this was before electronic calculators, it was a real pain in the arse to convert between the two; something we wasted an awful lot of time doing back then!
I no longer have a use for British weights and measures as I have lived in metricated Europe full time since 1999. No one over here would understand a reference to any non-metric quantity and it seems like my brain has abandoned them too. I can no longer relate to my weight or anyone else's other than in kilos. Lengths have to be in centimetres, metres or kilometres for me to be able to visualize them. Fuel consumption has to be expressed in litres/100 Km otherwise it means nothing to me.
However, in all professional contexts (except perhaps estate agents) Britain is completely metricated but for a few minor exceptions. (the use of inch sized galvanised steel barrel with its associated inch thread sizes is one). Oddly enough, even here in Luxembourg where I have lived since 2004, although absolutely everything in life is metric and has been for centuries, they still sell galvanised steel barrel in UK inch sizes with its associated inch sized 'British Standard Pipe' threads!