If you're doing high end 3D rendering and animation go with the precision the workstation graphics cards in them are designed for that type of work. The XPS would do the job just fine too but with the precision series you get the card that is custom tailored to rendering and animation and other such things as opposed to a gaming card in the XPS that can do the same thing but doesn't have the precision (pardon the pun) of a Quadro card with it's drivers.
Both will support 3D rendering and animation.
If you're earning a living doing 3D rendering and animation you'll want to skip the laptops and go straight for the desktop/workstation hardware.
If you're a student learning to run 3D rendering and animation it's going to probably come down to how much you can afford to spend on a laptop.