Avoid Lloyds TSB bank if you can - they refuse to accept a travel note/advisory/flag at all, and any ATM withdrawal in the US seems to trigger refusal/the card being blocked.

The worst thing about Lloyds TSB is that their fraud department (the only folks who can unblock debit/ATM/credit cards..) work UK office hours only, not much use if you're in Sydney or Los Angeles and needing some $$ for a taxi. They are absolutely unapologetic about it as well. They will attempt to contact you on your cell -- but this can be four-five hours later.

Every trip I make to the US has a matching huge roaming cell bill for getting the card unblocked on the first day.