Look at my sig, I think I have a decent opinion on it!
Anyway, the warrior (warriors are rx1's with a factory 136) is a stupid fun sled on trails because of the amount of power. If you want your arms stretched, that is the machine. It does require a higher seat and handlebar risers, in addition to the radiator cooler. (not required but suggested) Off trail, it is a beast... Lots of weight, not the best suspension if you get airborne, but enough power to get you through some deep stuff.
The Nytro on the other hand is much more like a true ditch banging sled. I had a '01 AC ZR 600 before, and they are actually very similar machines. If you get the Nytro airborne, you really don't even notice the landing, it is that smooth. The Nytro also has some decent kick off the line, but the warrior quickly passes it by 40 mph. My major mods to the nytro are a 136" track extension, radiator, and welded aluminum oil tank to replace the leaking OEM one. (warrior has the same tank, it just hasn't leaked yet.) Also, the nytro's have a timing chain tensioner that is prone to failure, and it is a pain to replace. If that hasn't been done, factor that cost in.
If I had to pick, I'd go with the Nytro (that is my sled, wife drives the warrior) I really don't care that much about speed or power, I like off trail and picking my way through the twisties. When we go riding, we do swap back and forth occasionally, and the warrior puts a stupid grin on my face every time! (at least until I get it stuck...)