I had no regrets getting my 2005 model over the 2004 even though I could have saved a few thousand. The additional capacities have paid for themselves and make this truck very competitive in towing and hauling (even against some newer models). I knew I would be keeping the truck long enough that a year difference in make will not change my selling price much, but I feel the model year changes will make it sell better than a 2004.
I hope my blabbing about my truck will help you decide which truck you will want.