I beg to differ.
Can it tune upper and lower injectors? (usefull for over 215HP)
ECU Editor - Yes
PCIII - sure if you buy a second PCIII. Same with PCV, you need a second (expensive module)
Can you tune part throttle, light load conditions (using IAP)
ECU Editor - yes
Power Commander - whats IAP?
Can you pull timing or add timing?
ECU Editor - Yes
PCIII - no, unless you buy an (expensive) ignition module. The PCIIIR used to do this, but they pulled that functionality so they could charge us more.
Can you do gear compensated fuel adjustments
ECU editor - yup
PC - $300 hub will allow you to do this.
Can you run multiple maps for motor / nitrous
ECU Editor - yes
PCIII / PCV - yes if you buy hub accessory
Can you progressively control nitrous
ECU editor - yes
Power Commander - uh, no..
Can you do autoshifting
ECU editor - yes
PCIII - requires hub. Don't know about the PCV.
ECU editor is not perfect, and if you are a dyno operator, it can be slow. There are still things that could be improved, but lets be clear, in that its ability to tune is pretty damn good.