Is there a quantifiable difference and is the cost of private education worthwhile?

It would seem that it is but the question is is this the right route to go down for society generally.

Money in someone's account cannot really be said to be a measure of deservingness of an elite education. All sorts of people have acquired money using all sort of shady means, and that includes peope in established economies.

However entry into such a system of elite education will no doubt lead to a far greater chance of being interviewed for upper middle class roles..in Accounting, Marketing, Law and Information Technology, Science and post graduation research positions for example. Similarly the Civil Service, quasi state bodies and think tanks as they are known in the UK