A: The EHIC and GHIC gives you the same access to emergency treatment that locals would receive, and typically covers up to 80% of Emergency Medical costs. It does not however cover Mountain Rescue, Repatriation, Personal Liability or cover your personal belongings.
Please note the new GHIC is currently not accepted in Iceland, Switzerland and Lichtenstein. Norway will accept a UK passport for the same level of cover. However, it is now accepted in Australia and New Zealand, where the EHIC is not.