You will be very happy with the 400 Explorer. My brother bought one the year before I bought my Sportsman, And I think its the better of the 2.
Faster, lighter, able to go through more slop (Lighter, stays on top)
Clearly the best full size buy in the ATV 4X4 market.
With normal use, and left mostly stock, its nearly bulletproof.
The chains are a little more Maint. in the long run, but not a big deal. The motor will not need a Piston and ring for years. My brother plows with his, and beats it to death on the weekends, not a single problem, 3 years running. If I had it to do over again, I would have bought the less expensive Explorer.

 

Great posts everyone, thank you all very much. In reality, the 250 would be just enough machine to handle the type of riding I do, but as I recall, I found myself pushing the quad to it's limits on numerous occasions, which isn't all bad,,,I find that I become a better rider when the bike or quad I am riding cann be pushed,,,rather than me just trying to hold on. I think the 400 is ideal, because of the snappier response, bigger tires, and updated styling (as compared to the 250. I often thought of putting a rad valve and pipe on the 250 when I owned it, but will probably leave the 400 bone stock. I actually use to ride a 96 Sport 400 (i think), and really loved the hit that the 400 motor produced. What I didn't like about that quad was it only had a hi range transmission. The way I ride, when I need 4wd, it is more often than not I also need to be in Lo Range on the tranny. That is exactly why the 400 has always appealed to me, because of it's power matched to a usable drivetrain. Not to mention the fact that I love the way a two stroke hits, the way a two stroke sounds, and the way a two stroke smells[img]i/expressions/face-icon-small-smile.gif[/img]. I guess it's in my blood since youth. I'm not knocking the 4 strokes at all,,,my brother rode a Magnum 500 last season, and I liked his ride alot,,,but for the money, I was riding the 250,,, and could just about hang with him in every situation. In the really tight stuff, my 250 was much less tiresome and easier to ride. By the way,,,the reliability everyone is posting about is incredible,,,,I only ride quads about 3 months a year during the cold winter season when it's too cold to ride other bikes,,,,so the top end on this 400 will probably last me at least 5 years,,,,that's awesome. Keep the posts coming about the 400,,,,I should have mine in a week or two,,,,in the mean time, I's like to hear more about your experiences with the 400, both positive and negative,,,Dave.