Yes there is little economy to be had and in Andorra too but at what price for the convenience?
BTW there is a used one with some dings in Germany for the tidy sum of @€980.... sheesh!
IMHO X-tank gives a total of 19 litres so reasonable range in EU anyways.
For beyond, you could always have a 3, 6 or 20 litre Desert Fox fuel bag which weigh very little empty for when it becomes necessary to extend your range.
NB illegal in EU and UK)