You obliviously have the 4x4 bug and you are upgrading to satisfy your want. How much more payments do you have to add . Di the math and find out how much you are our and if you are alright with it. 25 dollars less in payment does not means you are getting for free. If you can afford it, do it!!! Life's to short . If it is not worth it for you, then reconsider at a better opportunity.
Good luck !