The 400ex was my first ATV. I've had a bunch of SportBikes and was used to moving pretty fast, so I didn't want a 250ex or 300ex. Well, I can tell you that the 400ex is plenty fast enough and handles great. ATV's and street sportbikes are two totally different ball games, and I thought I'd be comfortable flying around on an ATV like my CBR900rr. I was wrong. The 400ex is sorta scary. I've had my 2002 400ex for a year now. I havn't raced it, jumped it higher than four feet high and never rolled/crashed it. I've found that I'm really not that interested in ATVs as I thought I'd be. There's no legal places to ride (at least not close and cost-free). It just sits in my garage. It has a little over 30 hours on it (changed the oil after each 10 hours of use). I'm going to sell it, since its just a waste of money.
My point is, don't buy a big new ATV, if you havn't really ridden one for a while yet. Get yourself a used 400ex (if you live near NJ, you can buy mine) and see how you like it. You'll get a great deal on a used 400ex, and if you find that its not for you, you can sell it for what you paid for it, instead of losing money like me. Also, I think after riding a 400ex, you'll probably settle in and like it just fine. Spend the money on good riding gear (complete set) and enjoy. If you get into racing and want something better, you'll have that peace of mind knowing you can sell your used 400ex for what you paid for it and then spend the money on a brand new racer (or just upgrade the 400ex w/ better suspension and a 440kit and be on your way).
Just a thought. Hope it helps.
PS. anyone near NJ interested in my 02' 400ex, email me at [email protected]