There's a lot to think about with nitrous though. You can/should only spray it within a certain RPM range (usually 3000+), and only at high throttles (wide open usually). If something goes bad with it, it seriously goes bad. Usually people use an arming switch, which engages the system and leaves the solenoids all up to the wide open throttle switch, so when your pedal is pushed down far enough, the nitrous and fuel starts spraying into the engine. As an added safety, most use a window switch, which only allows the system to be activated within that safe RPM range. The installation is quite simple on these kits usually.
Boost is the nicest form of power addition, as you retain or increase your normal fuel economy, and all of your normal around town driving is a lot more zippy and acceleration is easily had. Nitrous is only fun when you're wide open, whereas boost (supercharged or turbocharged) is fun all the time because it's always helping the engine breathe, it's just at higher throttles it's really building the power and making it OMGfun.
Back in the day (2005) when I had planned to spray, I was going to get a
Nitrous Express kit.