Isn't the answer kind of obvious? With a 250$ payment, you have several risk factors regarding time: Inflation, death or you losing your memory and therefore the password for your bank account. Bitcoin on the other hand have no short-term downside. You could sell 2.5 of them for a 20% loss after taxes and buy the MSCI World or another well diversified fund for the net 38,000$ you get. With an average value gain of 5% over 18 years, that would result in 91,000$ plus whatever that half Bitcoin will be worth.