One issue I have run into is the restoration of the encryption key if it is lost from the server. If you have a copy of the master it is possible to restore it and have access to you encrypted data but BOL make it sound easy but there are many steps that aren't in one place. I would practice a few times as it is easy to over write to information and render it useless.

If you find a better guide than BOL please post it as my notes have worked but are not complete.