I bought a Z66. It rides great, has autoleveling (great for trailers) AND best of all, has Positrac AND Traction control...
No wheel spinning.
I had a 4x4 before, in Michigan. When it gets slippery, the traction control keeps you under control. Sure it takes a little bit longer to get going, you do get going though. And no butt end spinouts because you punched the gas pedal..
As far as the added resale value, it costs more to begin with when you buy 4x4 also. Plus there's insurance costs too.