I have never owned a G8, but have rented them on numerous occasions. IMHO, I think they were horribly built. The doors rattle, the seats are uncomfortable, and the engines were underpowered. This is from a guy that has owned and driven Grand Prix's for the last 18 years. I keep looking for low mileage 2008 GP GXP's as that is one of my all time favorite cars to own and drive. I need to grab a few while they are still around to last me for the next 30 years.
I would HIGHLY recommend a 2006-2008 Grand Prix GXP.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold