mine is a 12/07 production 2008 4.8 and i have driven the dog-snot out of it for over 90K miles with no major issues.

it is buggy as far as some of the electronics: Sat Radio, Alarm, SOS System fixed mostly under warranty.

Body: one Daytime Running Light, one Window Regulator.

mechanically: hoses to the transmission were replaced as they were leaking, but i was up under it yesterday and the pan is dry and all seems fine 8K later.

look for a CPO '08 and you should be fine. IMO 3.0 may be more problematic early on and the 4.8 later........... valley coolant leak............. fingers crossed here........