is there rerally gonna be that much benefit from a stainless??

i have just bought a mk4 4 door estate and its all turbo'd with a cam and chip too but its totally boggo std on outside bar some cloverleaf alloys (soon to be swapped with mondy 15" or 14" steels and caps)
even had 'keepfit' windows and L style full interior bar the rs clocks


i would rather leave the std rs exhaust on but bloke has a full almost new magnex for 80 quid so i could get that while im pickin it up


but is the pref pipe gonna help much??, mite make u think ur goin quicker (cos it sounds it huh) but does it make any real difference