i've got the zxtuner header on mine, it works well if you have alot of other mods but if you only have a few engine mods you get a very marginal gain in power for quite a bit of money IMHO.
your better off spending the money on getting a decent intake manifold on a zetec, that is the real restriction on power.
the standard exhaust manifold flows quite well if you remove all the EGR and pulse crap from it.
