Performance Wise
 

I got a 2016 nismo and I was wondering what gives the best performance for an exhaust,not really worried about the money as im just generally curious what would be the best performance exhaust set up. Is it ark dts with fast intention long headers, or armytrix with fast intention long headers or is there an option 3 I dont know about

I think fast intentions catback and long tube give the best hp numbers

Depends. Mods on the intake side will affect which exhaust setup works best. Not many people go to the trouble/expense of modding the exhaust without modding the intake. Any of the better exhaust setups (many threads on this) and a good tune should be good enough for all but full-time racing applications. YMMV

stillen 3g since thats basically the best intake, ive seen many threads but I would find them little bias if it started from a vendor