It's totally possible to get a custom one made. It'll be some money though..
As per running N2O everyday, it wouldn't matter unless you're at WOT all day. If you rarely hit WOT then it won't cost any more than what it cost to buy and install. That is, unless you have a switch that allows you to shoot N2O before WOT and you're shooting it all the time.
Other than that, using a WOT switch will make it so that it only shoots when you actually need the speed.
I would venture to say that N2O gives more power than F/I for less money AND allows the relative conservation of fuel.
As per running N2O everyday, it wouldn't matter unless you're at WOT all day. If you rarely hit WOT then it won't cost any more than what it cost to buy and install. That is, unless you have a switch that allows you to shoot N2O before WOT and you're shooting it all the time.
Other than that, using a WOT switch will make it so that it only shoots when you actually need the speed.
I would venture to say that N2O gives more power than F/I for less money AND allows the relative conservation of fuel.