That kit is very labor intensive. You need to have lots of tools, a lift, a welder, and lots of time/know-how to install that kit yourself. If you don't, and have to pay someone to install it, plan on at least doubling the total cost.
Exactly. Also the On3 kit comes with very basic components. If I were ever to install a turbo, I certainly would buy a much better waste gate and BOV than is included in the On3 kit.
To the OP, honestly, if you want cheap effective power, you can't beat a wet nitrous kit. You can get a good quality kit with ALL of the safety features for less than $1000. You can make 350 rwhp pretty easily/safely with a kit like that, and I'd put money on it that you'd be more than happy with 350 rwhp for a good while.
Yep. Hard to beat the bang for the buck of NO2. If you're convinced in going FI, then look at a Vortech kit. They're very reasonably priced IMO.