Just bought our new to us 2010 G6 with 8000 plus miles last night.
Next year we will be getting it set up to tow behind our motorhome. Presently we tow a 2006 Malibu Maxx. We bought the G6 (4 cylinder) because it can be towed with all four wheels on the ground (4 down).
Since we haven't even had it a full day, we don't know much about it. But it seems like a pretty solid car from our lengthly test drive. Time will tell.