To be quite honest with you I have heard some bad things about Sub Zero from friends experiences with them. Such as cracked manifolds etc.
Like I have said to people asking the same question on this site, if you want a dyno tune, turbo/fuel pump/computer etc. got to
Brisbane Tuning and Turbo @ Wooloongabba. Great people, do excellent work for a good price, and will always steer you in the right direction.
If you are after an exhaust/filter/front mount etc. Then try 'Team Drift King Motorsport" at Aspley. Speak to Dan and he should be able to help you out at a good price.
Scott