I've been doing a lot of trail riding on my Blaster and some of my buddies 4 stroke ATV's and I just lie the way a 4 stroke as a smooth delevery of power and that low end torque to get over rocks and trees a lot easyer. On the open fields I wouldn't trade my Blaster for anything but I'm 6'3 and weigh 220lbs so I'm kinda cramped on a Blaster. I'm not going to get rid of it b/c my Son is 7 and my wife likes to ride it and in a few more years it will be good for my son. So here is what I'm looking for in a bike... must me a 4 stroke, with a reverse. We do a lot of riding where we don't know where we are going and when you hit a dead end it sucks having to get off and push. I"m open to all brands... and here are a few I'm looking at.... Raptor 700.. I don't want a 660 I've just heard to many things bad about them and really the price for a used one isn't that big of a differnece. KFX 450, not heard a lot about these but what I have read has been good. LTZ400, heard lots of good things about these as far as trail bikes... TRX400ex, this bike has been around a while so there has to be something right about it. I'm also opened to other suggestions. Please if you have any experance with any of these bikes leave your thoughts.