Hey Guys, long time reader, first time posting... I have a FG F6 ute and am looking at upgrading the exhaust system. My tuner recommends fitting a full Di Filippo system; 3-1/2" dump into twin 2-1/2" pipes and a hi-flow cat (not sure what size). Has anyone fitted one of these sytems to their vehicle and are they any good? I have noticed a lot of people on here are running a X-Force system, would this be a better choice? I am hoping to achieve 400-450rwkws with future mods such as aftermarket cooler, cold & hot side piping, 4" cai, larger 60lb injectors, upgraded actuator, surge tank/fuel pump, ugraded valve springs and tune. I am concerned the Di Filippo system may be too restrictive for my goal and was thinking a 4" dump and twin 2-1/2" system may be better suited? Thanks in advance for your help!