Car and Driver
GM’s timing could have been better. Powered by a 3.6-liter, 256-hp V6 engine that’s hooked up to a five-speed automatic transmission, the G8 gets only 17 miles per gallon in the city. The interior is spacious, the steering firm, and the handling excellent. But the gauges look cheesy, and the engine “sounds coarse when the throttle is put to the floor.”
This fantastic car is “probably the best that Pontiac has ever made”—even better than the Trans Am. The “nostril-like hood scoops” may look a bit over-the-top, but the construction is “rock solid.” If fuel prices remain high, the gas-profligate G8 may not seem like such a good deal. Fortunately, an “active fuel management” system shuts down four cylinders when power isn’t needed. We observed 32 mpg at 60 mph on the highway.

USA Today
This “big ol’ roomy and comfortable American sedan” doesn’t have the Dodge Charger’s muscle-car legacy, but it can go from zero to 60 in 5.3 seconds, a few ticks faster than today’s Charger. Sporty accoutrements include high-bolster bucket seats, firm suspension, an overhead camshaft similar to that of the Cadillac CTS, and a sports-mode gearbox. The big trunk makes it an attractive alternative to a crossover SUV or minivan.