the external wastegate holds boost better,no leaking,no boost spiking,you normaly put it in the centre of all four header pipes connect,and it sounds like i ainno it pushes the exhaust threw be4 so its loud and noisy i love itttbut that sonly when it opens ud no that!
U only get the noise with a screamer though, if its plumbed back into the downpipe its silent i think.
Do you have the vacuum line connected? and if so is it on the correct port of the external wastegate?yeah they are rite it makes a lovely noise when open and from my experiance boost comes on stronger with it since there are no leaks etc....question though what could stop one from opening? boost is at 15psi on tdo4