The Rb25 turbo upgrade thread in forced induction shows a few results with this turbo.
Its quite common to see 265-275rwkw at 16-17 psi
Power just seems to hit you when you want it whilst drifting i have found.
The GT30R (GT3076) is not the same turbo as the 3037s listed in the link above.
It is rated to the same power how ever has a .70a/r compressor cover usually found on the GT3040 etc rather then the .60 on the GT30R.