Thinking about it, it's probably all more or less meaningless now that it's not unusual for working class people to go to university?
I would assume you would need a big kitchen and probably stone floors to have an aga, but then they're not a million miles away from the old stoves that used to be present in old terraced cottages?
They sell vinyl in Sainsbury's now, but I don't know what that says about it.
I think the distinction is easy - is John Lewis normal or posh? If you think it's normal, you're middle class. If you think it's posh, you're working class.
Maybe matching coasters are working class because the middle classes have all those artfully mismatched faux vintage ones?