go external,they are used because of there quality,and accuracy(when set right on controller)thats why the rs200,audi s2,bently used them years ago,actuators are so hit and miss (old hat).for example -31 so strong that you get the boost delivered in a big thump.people who cant afford them or dont know how to use them slate them,at least you can run big boost and control where you want the power to come in.hope that helps,oh who do you come highly recommended by ?i just constantly see your comments being corrected