For long term storeage or safety critical equipment I would recomend the Energiser L91 litium AA cells, AFAIK the makers hold a watertight patent on this type of cell and no one can make a generic equivalent.

If you use a fair number of AA cells normally, then I suggest any reputable brand of alkaline cell, the lithiums are too costly for everyday use.
Here in the UK lithium AA cells are at least 4 times the price of alkalines, and in a typical flashlight or radio they dont give 4 times the service (they would probably give 4 times the service in very high drain applications such as digital cameras, or in extreme cold)

In a prolonged blackout, would you rather have 20 lithium cells, or 100 alkalines? the cost in £ or $ would be similar.
The 100 alkalines would give more hours light or radio listening.

If you use lots of batteries frequently, then any of the better brands of rechargeables are worth it, but remember to keep a stash of disposable cells in case grid or other power is not available for recharging.