I have the Janetty (sp) Racing 80hp injectors. They mad a VERY noticable difference in performance. I paid $700 + $700 corp deposit, which was refunded. The install was not that hard, but if you have an extra $300 laying around, pay a mechanic to do it. I was down to under 20 minutes to swap an injector out after the initial tear down, which I got down to about 20 minutes also. Been there, done that. You will need a few specialty tools if you do the swap yourself. Janetty's instructions were very good and easy to follow. But they mention nothing of the tools required to do the install. Some shorty/stubby wrenchces, torque wrenches (mentioned) and crow foot wrenches. Very tight fit towards the cab side of the motor, a real pain in the knees and lower back. If your not built like a monkey, pay someone to do the swap.
Mike