I used to have a DPR Stage 5 head on my NA SR20DE. I paid around $1200-1300 or so a few years ago. On an SR20DE a good head porting etc..will net you about 10-15 wheel hp. That is a substantial gain on an NA car but not on a turbo car.

If you have a turbo car spend that $1200 on something else like a turbo upgrade cams or downpipe and exhaust.

My NA SR20DE made 147 hp to the wheels with headwork and bolt ons. This was with stock cams. With JWT S3 cams I would have laid down about 175 hp to the wheels. The headwork will only give you large gains if you have agressive cams that will flow a lot more air.

Good luck