Do I need a camber kit???

I just lowered my 2007 Tahoe using DJM's kit, 2'' in the front and 4'' in the back, not sure if i like the way the truck sits as of yet as the rear sags a bit more then the front, but im told that it will level out better once my alignment is done. Not sure if thats true.........
What i really need to know is if i need a front camber kit?????? Does my truck have adjustments for the camber if its a 4 wheel drive????