The headstuds are a hit and miss in the early (03-04) 6.0s. Upgrading them is fairly expensive unless you can do it yourself. They cost less than 500 and 2500-4000 depending on who and where you get it done to install.
With that the 6.0 is a pretty rock solid engine and will hold the power your looking at and some. ARP is a good headstud brand, ATS is slightly more expensive but better I think. But the ARP will hold what your looking at and some.
The banks stuff is overpriced for what it is, but FOR banks products thats a decent deal. Exhaust will run you 500, intake 500, and chip 500. But banks ones are 700 exhaust, 700 chip.
Better bang for buck is headstuded, exhaust, and SCT w/ innovative.
The sct will give you around 400rwhp hot tune, and the banks will give you somewhere around 330 I'd guess. If you headstud either option, its automatically more reliable.