EBC can spool turbo up quicker by setting the gate preasue. which will only allow the waste gate to open at a set psi. A good manual valve will do the job though but as stated before turbo smart boost t's arnt much chop.
dude if your gonna be drivin a baby around in it dont bother. 3" from the turbz back is the way to go but thats gonna be too loud for a baby. back preasure and turbos dont mix so the 2.5" is a no go.