piston questions

I thought the stock pistons in a magnum engine were hypereutectic? Lots of them did towing and hauling duty for tons of miles .. what's so bad about a hyper piston for towing? I thought they were only bad news if using nitrous?
And I was wrong about those pistons my kid has out of his motor
They're not 116s. They're H405cp. I was just over there for something else and I had him dig them out. So being that they're not what I thought they were.... They ARE speed pro and they are hypereutectic, but not the ones I thought they were. So I guess that's out then.