You're not going to get much more from the TD04 turbo, so I have NO idea why they recomended the boost controller other than to fleece you. Assuming you have a full decat, your next move is to buy a VF34/35 turbo, 255 lhr fuel pump, 550cc injectors(from STi), STi intercooler and a further remap. Should see you around 330-340 bhp.