Arena DK / Warlock doubt

Arena combo doubt
Hello warmane, Ive recently found out that a mate of mine also played in Icecrown. He has a level 80 frost DK. I have a level 80 unholy DK and a level 80 affliction Warlock. We wanted to try some 2v2 arena ( maybe get a 3rd person and go 3v3). I know our classes arent ideal for arena but with work and real life stuff our free time isnt that good to level up a new class at least for now, so for the time being, what would be the best combo regarding our limitations? Get the 2 dks together or the DK with the Warlock? Thanks in advance for the replies!