And I buy petrol in litres, drink wine by the litre ..
the point I was trying to make in my previous rambling post was that we use metric measurements (apart from miles and pints of beer/milk) but that apart from sales and professional transactions we don't use them in general conversation much. In my experience this applies to the younger generation as well. We use a mixture of units, sometimes together (a metre of 2" by 4" timber).
Television and monitor screen sizes are expressed in inches, car engine sizes in cc or litres. Arbitary and approximate measurements tend to be expressed in imperial - "The pub is 500 yards from the junction.", whereas specific regulated measurements such as in international sports (athletics, swimming, rugby, soccer, etc,) are in metric, presumably in US as well.
Since the change to Celsius (which I still refer to as Centigrade) is only just moving into the language after 30 years, we may need to wait a while. Even then I expect that many of today's imperial expressions ("give him an inch and he'll take a mile", "he hasn't an ounce of sense") will remain.