After the first three months we rang them, no problems, apart from the expense of international telephone calls.
After six months we rang them again. Nationwide now said they didn't need us to ring. We checked with the wise and wonderful on Motorhome Facts Forum and they confirmed that this wasn't necessary. Alliance and Leicester now say we need to ring them every nine weeks!
We use on-line banking when ever safe and possible. Alliance and Leicester blocked access in Slovenia, as they don't consider this a safe country to allow internet access. We have been able to access Nationwide everywhere.
Slovenia was the only country we had some problems with cash machines; our cards did not work in all the cash machines we came across.