Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.
dons vs: I agree mostly with what you say apart from 1 thing, that being rods handling a specified amount of HP.
Revs is what will kill a rod, not outright HP. You could safely make 500+ on a set of A9L's if revs are kept to a minimum, its when you start revving a motor hard when rods will stretch and break. H-beams are a stronger rod due to their design and will allow for higher revs whilst stretching and not suffer from breakage or un-roundness of the journal. I've seen I-beam rods last in 550hp motors and when pulled down, they are like new. Preparation is the key to having it last, balancing of the drivetrain is what is paramount to keeping an engine alive.
Hope this helps.