We switched to Halifax a couple of months ago after being with First Direct for 15 years.First Direct are just the same as other banks in what you can get out of them,their big plus is their customer service,we always found it first class.No pressing option this that or the other,just dialled and within seconds you were speaking to someone from the UK.
At least with Halifax we got £100 for switching(that £100 was available the day we filled the application form in at the branch)and you get £5 a month credit(not much I know but more than we ever got with FD) for paying over £750 a month in,have at least 2 direct debits and are in credit)We never go overdrawn so overdraft charges don't bother us.
The downside is you have to press a few options before you can speak to someone(UK based)
Regards switching,it was very easy,its all done for you and everything switched over on the day we agreed on.