Besides the Castrol, Pennzoil, QuakerState, and Amsoil already mentioned, don't forget the Idemitsu, Kendall, Advantage, BG, Excel, Schaeffers, and Eneos ATFs. Make sure that the bottle says universal or multivehicle ATF.
I do recommend regular drain/refills if you plan on keeping the car a long time. Hyundai's tend to beat ATF into oblivion quickly.
I also have a couple of Hyundai's running ATF+4, which might also be considered an option.