I have not ridden a DS650 or Rappy 700R, and off of the top of my head that is all I have not ridden sport wise. But I have heard that the DS650 is very plush and comfy for riders, my only concern for wooded trail use would be weight and size, so I would eliminate that one for wooded trails. The 450's are stiff so those wouldn't be good either for your use.

I'd say the Z400 and Raptor 660R have some of the plushest suspensions that could be used for trails. The Rappy might be more power than you are wanting, but it does have a nice ride to it. My only complaint about the 660's is that they are a little narrow making them tippy for a rider without a whole lot of experience. The Z400 has a very light feel to it, turns easy and doesn't beat you up on rough terrain. Like I said, the Z400 is like a more performance oriented 400ex.

I recommend another 400ex or a Z400 for you and your kid, they will both last a long time for you guys. Since you already have a 400ex, I would get the Z400 just to have a little something different. If you do decide you want a "cream of the crop" ride, I would consider the Raptor 700R, I really think that is going to be a great trail machine even tho I havn't ridden one myself, YET![img]i/expressions/face-icon-small-wink.gif[/img]