I now have a blitz SBC-ID, decat and nurspec on my UK spec. Im finding that theres normal levels of performance below 4500rpm and then once it hits 4500rpm it really had a kick. This is completely different to my import which used to kick at about 3000rpm.   The SBC shows that turbo1 is making boost (up to about 0.6 or so), and the second turbo can happily hit 1.2bar, but below 4500rpm theres really no major acceleration. I can just about keep it in the power band if I rev to red line each time