How strong they are depends on you definition of strong.

A hyper will handle more force before the metal deflects than a forged piston will, however while the forged one will just distort a little the hyper one will shatter like glass.

I had a set in my old 402 stroker and we machined the reverse dome off them and they were incredibly hard to machine. The machinist set a TRW forged in the lathe to show me how much softer it was and it was amazeing the differance. Because of the way a forged piston absorbs the deflection by bending it is more forgiving when it detonates, the hyper will shatter kinda like glass when it reaches its limit, the trick is to not excedd the limit by detonateing it

The harder metal deflects less under normal loading, that is one reason you can run a tighter bore clearance but the main reason is they don't expand as much because of the nature of the alloy. Because of that they will have more piston slap if they run the same clearance as an identicle forged piston, however if you run the tighter clearance that they recomend you will have less piston slap noise.

As for your motor I say run them, be carefull about the top ring gap in particular and be carefull on the tune to not detonate it and you will be fine.