i know people get tired of hearing this but:
its depends on what you plan to do with your car?
I have used
top gun
nitrous express
compucar
if its to be street driven, and ocasionally used to run at the track...then nitrous is what ya want! Crank open a bottle, plug in your power source , and bust someones tail!
and personally think the system I liked best was the compucar "bag of nitrous"
its a dry system, its hidden(its bolted to a board in a gym bag that you can easily slip behind the passenger seat in the rear floor board, and it will net you 100 hp or so at the push of a button. It would work great with an automatic too........just remember to not engage it below 3200 rpm, and the best part with this system is you only have one solonoid, one nitrous line (no fuel line) it will get its fuel from the injectors and the temp air sensor. It has a push button mounted on a curly cord, and a power source cord that is also a curly cord that plugs into a cigerette lighter for the power source. The biggest pain is when you have to run the nylon line to the front side of your air filter, and adjust your timing.
I've personally owned three of these systems and currently own one.....once my buddys saw this system they had to have one, so I sold mine and bought another one each time. I ran my systems on my 1994 cobra (many bottles feed thru that engine) without any problems, and on my 79 LX coupe that I stuck EFI on with a 5-speed etc... My current system isnt installed yet, but if my brother in law keeps mouthin off with his "RED LINE" edition Saturn ION with supercharger.........I'll probably install it and smoke em!
holcomb motorsports sells it for around $380