You get a weird wastegate chatter in the EVO and the phsssst noise from the dump valve is more
prevalent, more phsssst is good

. The chatter put me off at first and i took it out, as Darron explained there is more airflow hence the noise, now putting it back

. Dont think you get this with the AGP though. Cant say i notice any performance gains, but every little helps.
kEVO