04StreetF150

Okay guys so I'm looking into getting some LT headers and I'm not sure which brands are better or what is necessary to install. I heard you need a tune to run them at the best performance is this true? Also what prices am I looking into? What other modifications will I need such as Hi-flo cats and x and y pipes? A detailed response will be appreciated!
Looking into these as well: http://pacesetterexhaust.com/ford-f1...s-70-2229.aspx