No you dont need it. Crutchfield just makes you buy it so you still have door chimes as a security feature. So buy the head-unit elsewhere if you dont wanna pay the extra 60 bucks. I said screw it, and just bought the PAC because they already give you vehicle specific mounting hardware, atennae adapter, etc.
Crutchfield makes it so you dont have to search around for many different things.
They include it all.
The PAC doesnt lose your remote start, all it does is like a midway between the new head-unit harness and the vehicles harness, and it has an internal chime.
2006 G6 GT
Mods so far: Black arrow overlays, Chrome recessed grilles, Blue LED license plate light, Blue LED reverse lights, Smoked tails, 20% Tint all around, Red led's for the interior, White led dome and map lights.
Sound System: 4 Infinity Kappa component speakers, 2 Amps (950w total) and 2 10" Kenwood KFC subwoofers, 7" touch screen Pioneer DVD
Performance: Mobile 1 oil, Mobile 1 oil filter