NIStune all the way, stay away from CRed, so not happy with their Haltech install on my wagon and the butchering of my loom they did.
Removing it in favour of NIStune (had a hiccup with a spare ECU that didn't work ) soon.
Send me a PM, I can get NIStune boards and I have a mate that fits them for me and will probably work for alcohol
Further to things said above, Haltech is not a piggyback BUT when fitting them to our auto cars (my engine/transmission setup is pretty much the same as yours but 4WD) they have to be wired in as a piggyback. The TCM isn't a seperate unit like the older autos, it is part of the ECU which means the stock ECU has to remain to control the gearbox. This is how mine was done and they did some other dodgy stuff like changed the water temp sensor to suit the Haltech which screwed up things controlled by the stock ECU that need certain temperatures to operate (VCT for example, would never engage because the stock ECU was seeing the water temp as 65deg instead of 85deg).
Also, my NIStune tuners of choice in WA would be Hyperdrive and AllStar Garage.