While any AAxx hand is great to have in Omaha, be sure never to overplay your hand just because you have AA. If you're heads up, you can play it somewhat fast and loose preflop, and maybe even get all of your money in the middle before the flop; but if it's a multi-way pot and you can't get people to fold,
proceed with caution.
I can't even begin to count the number of people I've busted, or have seen go bust, by overplaying AA with 2 other rags, simply because they thought that just because they have AA, they're top dog; no matter what the board reads. This happens more times than not because players are not used to Omaha, and they have a hard time transitioning from hold'em. AA carries much more weight in hold'em than Omaha, for obvious reasons..
The key is to pay attention to how you opponent(s) are betting and/or raising after the flop and whether or not it's a draw heavy, or otherwise scary board. It's quite possible that they either have a strong drawing hand (flush, straight, etc) or have already flopped a set.
If they have a strong drawing hand, then you're in a coinflip, and if they've flopped a set, then you're all but drawing dead and hoping to hit one of the two remaining aces; which would make you around a 9:1 underdog after the flop.
imo, the top omaha starting hands would look more like:
AAKK down to AAJJ double suited
KKxx double suited, etc.
Any 4 cards in a run - e.g.: 9TJQ (extra points if you're double suited)
...and so on...
ps: I actually cringe when I get dealt a hand like AA92 that includes all 4 suits, especially when I'm UTG and the table is playing tight. At a tight table, most of the time the best you can do is bet pot and hope someone re-raises you, or you're going to end up with 4+ people in the pot...lol....
But on the other hand if you're at a loose aggressive table, your best bet is to limp and hope for someone to raise so you can break off a pot raise when it gets back around to you.