If Iceland goes bust, then there won't be any money to pay the first €20,887.
The Financial Services Compensation Scheme only pays out anything in excess of the first €20,887. So if you had £50,000 with Icesave you may only get back £33,767 (£50,000 - £16,223).
Is it therefore best to stick to UK banks where all of your £50k is covered by the financial services compensation scheme?