I'd rather have Glen Davis, because he is a more of a scorer. His rebounding needs work, but that will come in time.
We already have Perk, and Shelden is doing a fine job backing him up.
I can see why some would chose Marc Gasol, though. He is a physical low post presence and appears to be coming into his own, though.
Which leads me to believe that maybe I was beating up the Lakers too much for my perceived one-sided trade to get Pau Gasol. It has taken some time, but Marc is developing into a solid starting center.
But still I would take Glen Davis.