I have had my e-Aurora go in a few times now (due to failed ESC), and it is very durable (at least with the light 4400mAh TP lipos I am using).
But the Aurora is not meant to be a tank. It is meant to be repaired easily. I'm not saying it is flimsy. But when you crash, stuff breaks. However when you crash an Aurora, you can have it flying again in no time because it is very easy (and quick) to repair. The sacrificial tabs for the canopy mounts tend to save the frames, as do the landing gear. The kinetic energy of a crash has to go somewhere.
From a design standpoint, it is my opinion that the Aurora trumps the Trex easily. Besides, it is much better looking. But structurally, the Trex is probably stronger--while at the same time being heavier and more difficult to repair.
There is a circle. Thicker materials require bigger motors which require bigger batteries which require thicker materials--and on and on.
Now there is the guy who is running a 14S Trex 700 with monster horsepower (Beast?). I saw this guy at IRCHA flying. You could hear the heli from a mile away with the blades making a roar sounding like a P-51 Mustang. The Trex 700 can handle this kind of modification where the Aurora cannot. The Aurora is light and spindly and not designed for monster setups. I recommend 4200 to 4400mAh batteries as they are lighter (even though the new frames allow 5000mAh packs to fit easily). A light helicopter is good. It autos gently, and can be thrown around more easily. Besides, the batteries can be charged faster.
Don't buy an e-Aurora thinking you can put one of those 8HP Steve Neu motors in it along with 5500mAh lipos. Plan on a lighter setup.
Scorpion Power Systems
Thunder Power RC