Chps can be good, or very bad. Bad: Some send false info. to the brains of the car, causing lots of problems. Most do little, if nothing at all. And, they usually only do one job, as in, just getting more spark from the plugs. Good: Some are kind of cheap(no ebay unless you want bad #1), some do add hp( but most of the time like 5hp or less). The G-force chip ive never heard of. But the jet chip I know adds a little hp, not much. I would go with the ECU tune. Resonable hp gains, more throttle response, no granny controls, no speed limiter( i think), and you run more rpms. It would be so much worth it, and you know for shure its not confusing your car and causing problems. But, you may not see that 30hp gain that chips gaurantee you will get. lol
2006 G6 GTP: 4speed auto, intake resonater delete, mild weight reduction, some custom work, lol.