Here are my results: R34 GTR, stock turbos vs -5s
At 0.9Bar, the -5s are behind in response till 4400RPM. The most they are behind at any point is ~600RPM. In a six speed, below 4000RPM is just for cruising in traffic anyway.
I really cant tell that it is laggier or anything, especially when it comes on boost at the higher boost setting