I can see that you go no answers to your question, and you most likely aren't still in the market for a vehicle, but let me say that I have had an Xterra for about 8 years now and it's been a superb vehicle. It's got 92k miles on it and I've done very little other than routine maintenance to keep it going.
And even though mine is not a Pro 4x, it still has done everything that I've asked of it off-road.
I'm sure the Pro4x would be the same way. If you are still looking for one, I don't think you can go wrong.