And MBNA card transfers are not always accepted by other card issuers!
They usually have a mutual agreement with each other to prevent card hoppers doing this every other month.
They'll check out your recent borrowing on your credit file as well, so if you've been jumping around from card to card or have been late with even one payment somewhere else they'll use that to decline your application.
I'd go to your bank and sort the overdraft option instead; tell them it's for a bike neccessary to get to work etc.
And good luck with the 5EB R6 lol