DrakeSavory

2 hours ago, cinereus said:

Why? It's only £15k. Your car's probably worth more (if marginally harder to steal). And 40kg is a real pain to carry on flights before you even consider the environmental cost.

Do you have to declare how much you are traveling with when in the UK?  In the US we do if the value of your cash, metals, etc. is $10,000 or more so you have to advertise to the authorities that you are ripe for having your PMs seized (stolen under civil asset forfeiture).