Well its is obvious. I have been in that situation many times. It seems for me that my AK never seems to arrive. Having the QQ preflop is the way to go because you already made your set and your opponent has to hope for an A or K. I see the odds being in the favor of the QQ. Good luck
Against most part of the hands AK has NOT 75% equity.Talking about an all-in pre-flop situation, AK has something close to 75% of equity against most part of the hands, but against pocket pairs up to QQ, AK has 45% (which is really good, anyway). If we are with an AK against KK or AA, the equity drops a lot, specially against AA.
So answering your question:
In all-in pre-flop QQ is better (but not too much)...
Against most part of the hands AK has NOT 75% equity.