Depends where you're coming from. Visitors from other EU countries (and the UK, for now) will use their existing data plan, since the EU enforces free roaming a

Depends where you're coming from. Visitors from other EU countries (and the UK, for now) will use their existing data plan, since the EU enforces free roaming amongst member countries. If I was coming from elsewhere, I would likely do the same, unless I'd be there long enough to justify buying a local SIM card.