Seriously they aren't just looking for academics, some firms are exceptionally choosy but I guess it depends who you apply to. If your academic reference predicts you for a 2.1 or more, which is what they ask if its predicted, which OK if you have straight 40s wont wash on them, you should be fine. Seriously dont fret about it but dont just aim for the very cream of firms because odds on they will shoot you down, not because you are bad ... but because they have so many good applicants.