We bought our Armada new in Aug 04. Loved it from the start. Great power, tons of space. Had the usual brake issues, dealer handled it for free. Squeaky A/C fan also fixed free. Over 54K miles now and still going strong. Used it to shuttle 5 men for weekend trip and all commented on how big it is inside. MPG is no worse than other big SUVs, so I don't know why people complain. You know what to expect when you buy these things. We plan to keep the Armada at least another 5 years if all goes well. Why replace such a fantastic vehicle?
Interior space, engine power, luggage capacity (great for tons of camping gear).
If Nissan produced a hybrid version of the Armada, I'd consider upgrading. Space dividers in the big center console would help organize. As it is, you have to dig through all the stuff you dumped in there to find that one item on the bottom.