well it's about $500-$600 for a N2O system and you're getting anywhere between 25-75 HP.. you're not adding on all the weight of an intercooler, turbo, and it's a lot simpler to install, and you even get a cool little button to push.
with turbo it's 3k and up, you still get to adjust the HP gain anywhere between -something if it breaks down, to lets say 200HP to keep it sane. If you're not willing to DIY, there's a s*** load of install costs. tuning is a b****. turbo fans are delicate and if you mess one up it's maddd expensive.
BUT. you get the blow off noise which is an expensive commodity, you get boost all the time, and there's something more satisfying about seeing a turbo under your hood than a bunch of blue N2O lines and a bottle in your trunk.
i'd go turbo just becacuse with N2O it feels cheap to press a button to go fast...
is there a way to go turbo AND have nitrous?