Let's do some maths
Thats $3500 without a tune or installation, with tune and installation of all that you'll be looking at $6000 minimum for a total gain of anywhere from 10rwkw to 30rwkw. lets be generous and say an average of 20rwkw, thats $300 per kw which is a %0.57 power increase... kerb weight of 1758 + driver, lets say you're an average 75kg so 1833kg, that gives the car a power to weight of around 10.4 (W
)
Let's say %15 drivetrain loss for manual. thats 23kw @ the engine. so that brings the new power to weight to 9.25:1, really not worth it.
You know the VN v6 commodore had the same power to weight ratio as the VE ? you also need to take into consideration power bands aswell.
alloytech's make all their power in the top end due to DOCH, in a large heavy car its not soo good for going fast because you can't get off the line fast.
Take a LS1 or L98 etc, Full exhaust will cost around $2000 + fitting, say $2200 for good measure and net anywhere from 30-40rwkw, lets call it 35rwkw, thats $62 per kw and has a much wider power band
I'd never EVER buy a cam without seeing the profile specifications, they don't even list duration or lift...
speaking from experience, don't do it. just wait till you can start with a better platform.