[Katana]

Yeah johnny, i bought a set of 10-19mm sockets but they need a 3/8" connector, weird.

Here in England we are caught between metric and imperial, switching between them frequently.
When it's a hot day (becoming a rare thing) most people won't say it's 30c they use fahrenheit, bigger number sound hotter, same thing when it's freezing cold, we won't use fahrenheit and switch back to celsius because the smaller number sounds colder. Even weather reports do it.

Shops are meant to be completely metric, and i'd say most newer ones are, but some still use imperial or both, it's an EU regulation but not really enforced for smaller companies.

I tend to switch between them depending on the situation, when driving everything is in miles, since all the road signs are in miles that makes sense. for small liquid measures i prefer millilitres and litres, but bigger ones in UK Gallons. You can't buy anything in gallons anymore though, the only imperial liquid measurement still used on a large scale is the pint for alcohol, that's almost sacred here, 568ml of lager doesn't sound the same as i'll have a pint of your best.

When you tell someone how tall you are you use feet/inches, and when you say how much you weigh you use stones/lbs, i think stones are only used in england still, 1st=14lbs.
When i want to be precise and do calculation i use metric, base 10 measurements are easier to do, something like 16.6cm (166mm) + 25.4cm (254mm) is easier than 5" 9/16 + 10" 5/8.

I get the feeling i'm the last of that generation though, the only thing taught in school now is metric, most stuff is in metric and the small amount of things left in it aren't hard to convert in the head. I've learnt to convert between 90% metric/imp stuff because it was necessary, you could get waway with only knowing miles/mph and pints in england and have no real trouble anymore.