Obviously after the event, but I would have cashed out, simply because it was enough to buy 2 fairly decent 3 bed houses up here and have enough left over for a new car. Plus, would I put £250k on any horse to win, the answer is no. I know the value wasn't great, but the amount has to be taken into consideration, if it was £250 cashout value and £500 if it won, I would let it run, as £250 wouldn't make that much difference to my life, £250k would.
Having said that, if I was rich enough for £250k to have the same sort of value to me as £250 would today, then I would have probably let it run, but lets be honest, I don't think that would apply to many people.