I haven't been watching the Forum much:
Bought a C6 Vette and have been busy with that for last 3 months

With all the posts, and most of them positive:
I'm surprised the Predator is still be discussed like it's undecided whether it makes an improvement or not.
I only have the K&N air filter for mods and run the 93 Predator Performance tune in my EXT.
It Makes A Difference in a Very Good way

Any info about not being able to program the Trans is true but,.. the Trans shifts better and.. Less Often with the Tune installed.
The reason being is the Trans senses when the engine is starting to Lug/Struggle when more gas is given, so in turn, it down shifts to let the engine make more power with more RPM.
With the Tune installed, the Motor makes more power easier and the Trans does not sense the engine Lugging as much so, it does not down shift as much.
I took my Tune out of the EXT a while back to update it for the Vette.
I didn't put it back in and drove to the moutains, 200 mile drive.
I had forgotten how much the EXT down shifted without the Tune.
Also for that reason I noticed less MPG.

With that in mind, as far as Modifying the Tune to make it even Better....
I learned a lot on the Vette Forum under the C6 Scan & Tune section.
It's invloved and time consuming so not going to post all the info.
But, doing so makes a BIG improvment over the stock Performance Tune which is still a Nice improvement.
Each vehicle has to be done to itself, can't just take reading from someone elses Tune and put them in.
It involves running the vehicle, making a Log, saving the log, printing it out, reading it to make adjustments to what you want it to do to make it better.
Then, .. do it all again to test the results and most likely make more changes
Anyway, to anyone getting the Predator Tuner and installing it:
Be aware, there is a "Slight" instant noticable difference but,...
it takes a few miles, about 100 or so for the Tune to really take hold.
The ECM has to learn the new Program and Peformance and enjoyment will progressively get Better.
Check out some of the info as I mentioned on the Vette Forum, Scan & Tune section.