Provided the truck is in good condition, that combo actually had the most power and most gears for that era I believe, compared to the 5.4 ford and 5.3 GM.
However with any 10-15 year old vehicle, within reason, the miles, condition, and maintenance are likely more important than the brand, 20hp or an extra gear.
Have 06 and 07 Dodges currently with a combined 300k and climbing and I don't feel either of them are "used up" or on their last legs. Both have been relatively trouble free, IMO.
Fwiw, I'm sure I could say the same about a Ford or Chevy from that era as well. All were pretty decent.