I'd have to halfway disagree. I know next to nothing about nitrous so can't comment on it. Boost however... properly tuned, hyper pistons will handle more horsepower than the stock block will. The block will be the limiting factor (450 RWHP rule of thumb).
Other considerations would be rods, bearings, as with all the other internals.
Don't expect to run out and install a power adder to make 450 rear wheel on the stock combination. They're just not designed for it. 300 rear wheel HP is a reasonable goal with boost over a stock combo.