Nitrous will cost about the same as a supercharger and alot more hassle. Cost me thousands to get it running right. An aftermarket ecu is required to make it run "correctly"
A pre 2006 will barely scrape 300bhp with the above mods. A post 2006 will make slightly more, a post 2007 will make about 315-330ish.
Be prepared for big bills for these mods etc. the zed isn't a cheap car to do this to