It's not even measurable. Customers who are running our race fmic and the stock turbo have not noticed any difference in spool or lag. Although our intercooler is of a higher quality than the mishi (not hating, I ran the J line on my focus st).
I would step right up to your Race IC, even on the chance of
minor pressure drop, or
minute lag on the stock turbo setup, but I am not too sure IF I want to go the crash bar route just yet.
Yes, I know you make the stock fit deal, but, I think that the CP-E is tops at that fitment/app, and
if I go DHM, it is going to be full on RACE IC, or nothing else.
Obviously, if I went to ANY of your BT kits, the full Race IC/crash bar setup is requisite.