I will choose Bitcoin. This is the currency here to stay for a long long time. Surely, in a year or two it will establish itself in the e-commerce market and then you will be able to buy from bitcoins, which you cannot do it by keeping gold.
Bitcoin and gold are having different functions, and therefore I don't know whether we can compare both of them. Bitcoin is a currency, which should be used for day-to-day expenses. On the other hand, gold is an investment asset, for which the main function is the protection of wealth. (That said, Bitcoin can be used for protecting the wealth as well, but it is it's secondary function).
Well gold has been used for day-to-day bargains. It is still being functioned as the same in some countries. But soon the gold-mines will get exhausted and most of the gold we will see will be either in government banks or in computers. But bitcoin or a crytocurrecy will stay.