I researched heavily before I bought, looking at 300 ex & 400ex's, and warriors before I decided on my Scrambler. I knew full well that it was going to be modded before I bought it. I wanted a hot rod to play with out in the garage between the weekends. I had an RCR Stage 1 kit on the way before I even bought it...
HP gains are pretty easy and aren't too expensive when you look at dollars spent vs. HP gained.
For my type of riding I would not had been happy with a 500 either 2X4 or 4X4. You won't find anyone on this forum that ACTUALLY OWNS a 400 that doesn't like them.

 

Here's my two bits, and keep in mind this is just my opinion not gospel and I don't want to offend any body.
The Scrambler is an nice machine but if you don't get it with 4x4 you will have no advantage over the 400EX you were considering. In my opinion just the addition of the 4x4 changes the entire class of machine to put it in and compare it against. As a 2wd trail machine it's still capeable and is a nice easy to ride machine but it's kind of a pig. As a 4x4 it's THE fastest, sportiest, best looking thing you have to choose from. A 2x4 scrambler is still a decent machine but it's heavy and the suspension just isn't up to par with many of the lighter 2wd sport models like the 400EX. The 'push button 4x4' is by far the coolest feature especially when it comes to low traction situations, without this you will just have an overweight under-suspended sport machine that wont go very well when the going gets extra steep or sloppy.
About the engine, the 500 has got more torque and I would say would work better for slower more technical kind of riding where you would need your power down low. The 400 (the one I have) likes to RUN! It still has a decent amount of torque down low, but it really shines when you can get her out and open her up. I would say it has phenominal mid and upper range power, especially if you pipe it (a must do) with something like Rick Ritter's Stage 1 kit.

So as a recap: As a 4x4 it's head and shoulders above anything else out there currently available. As a 2x4 you have a whole lot of other machines you can and should compare it against, it still rocks but it has alot of other competition that is lighter and way better suspended. Since I got my Raptor the only time my Scrambler gets ridden is when I need 4x4 to get around as the Scram will literally ride circles around it in even a few inches of snow.
That's my opinion, take it for the few cents it's worth

'01 Blue Raptor '00 Trailblazer '99 Scram 400 4x4 w/RCR Mods

 

Very well put DuneJammer...my thoughts exactly!

 

I think even a 2x4 Scrambler has its advantages over a 400 ex. Although not as sport oriented you are still getting liquid cooling, reverse, a larger gas tank for longer runs, and has a much higher ground clearance. And it will still be a better mudder simply because of the larger tires.

 

If you buy a scrambler get the 4x4. This is the best reason to buy the scrambler. The only sport that is a 4x4.

 

That is exactally why I bought a scrambler 400 2x4, for one it's a two stroke 400...you don't see that anymore, two...side by side it makes the 400ex look like an LT 80, and third it has REVERSE!!!

I don't know of any other company that makes a 2x4 as versitile as polaris does.

LONG LIVE POLARIS!!!

2000 SCRAMBLER 400 2X4

SCRAMDADDY400

 

What a great post! Real people with real Quads! I have a SP500 H.O. I'm trying to squeeze a few more horses out of and it's hard!! That 400 has so much potential, but somebody goofed when they said it was liquid cooled...
I think the 4x4 argument is a good one. There are better sport quads out there, lighter,
better suspension. But only the Raptor and DS650 are faster, okay the Banshee too. The Yamahas demand modification, they are like "kit quads".
The thing about Polaris is they handle great and are easy to ride. What is the difference in weight between the composite floorboard arrangement on a Polaris and footpegs plus nerfbars plus netting etc? The Polaris arrangement may not be motocross style but.. works great. Polaris does have a weight problem. If you are a hard core sport rider you should consider one of these other rides, but the 400EX isn't competitive with these hot new rides anymore either. One Quad that can do it all is the 4x4 400 Scrambler, it only weighs a little more than the 2x4, and is a great compromise. Give up a little to gain a lot.

 

Fourlix, are you talking about the 400 Scrambler engine that has potential, because I'm pretty sure those are liquid cooled.

99 Blaster

00 e-ton sierra 90

 

You are correct sir, oops, I did it again. I checked the Polaris Site to make sure, I don't hang with any Scramblers. The 400 is liquid cooled, but why is there no 4x4 Scrambler 400 in the 2001 lineup? Here we are touting its' virtues as the great all-around machine,,
and its been discontinued? Please tell me I'm wrong..

 

Fourlix...you are right. The 400 4x4 was discontinued in 2001. It must be a sales figure thing. I love the Scrambler400 4x4 but see tons more of the 500 out on the trail. More people seem to like 4-strokes...The ones that have the 400's are the riders more into speed and performance.

Brian