I was in the same boat, after much thinking, I decided I have never owned a car this long, purchased it new, and since I still like it we have decided to built it up 'real' good.
And it will be cheaper than buying a new 5.0.
Besides, I cannot imagine buying a 5.0 now not knowing what the new model will look like. I would rather wait a year to find out. Besides, parts are cheap and these things are easy to work on.