Here is my .05 worth. I own both a 4.4 and a 4.6. Both are 03s with 103k and 89k miles respectively. The 4.4 has proven to have better dependability, better mileage and not as expensive to maintain.

You gotta love the 4.6 tho, it is classic, more rare, more fun to drive, and has a much higher cool quotient .

How about you run an add with both cars pictured, ask the same price with full disclosure for both and let the buyer determine which one you keep. Let's say 4 out of 5 potential buyers are more interested in the 4.6 then that is the one you keep.

Best of luck on your choice.