From my own experience having kept both species together in a tank where they accepted each other but also fought skirmishes occasionally, the edge goes to the dorado due to speed and accuracy. The aimara has a horrible temper but dorado is more a police patrolling territory. They usually keep to themselves since dorado is a mid-water swimmer while aimara lurks in bottom as an apex ambush predator. Their usual spit spats is an occurrence from the dorado pushing his patrolling a tad bit too close for comfort for the aimara. Once they do get into a fight, the dorado easily out maneuvers the aimara and can easily get several bites in before the aimara can land a big blow. Indeed the aimara bite is quite fierce but if are are talking about sub adult fish around 40cm which is what both of my fish were, their bites are not fatal. Both are robust fish, dorados are like an underwater torpedo made of pure muscle and can actually take quite a bit of damage. My aimara almost lost one of his eyes from a **** combo by the dorado once before and to my amazement, it recovered nicely. If both fish are adult, it would probably be a matter of who struck first and at which part of the body but I really can’t see the aimara doing 360 turns and dashes from different water levels in the way the dorado does. If any of you has kept dorado in a large body of water you can relate to just how fast they are. Even at subadults and juveniles, they are much much tougher than ATF/GATF which only start taking on confidence when they mature. Ultimately, each specimen has their own personality and temperament as you all know. that being said, I would rather take my odds of placing my hand in the tank with dorados than to tempt a lurking aimara. (Have been bit through the bag by mine the day I got it)