Got mine today and installed it...man what can i say...im impressed...didn't notice it spike at all, unlike my old shitty turbosmart one which spiked like no tomorrow, and boost seems to build quicker, and holds very well, think it only dropped like 0.5 psi at over 5000rpm. Can't wait to get it on the dyno to see the difference in the power curve beacuse of the different boost response. I'll keep yal posted as to how it goes. Great work by mark!