Small bikes are great, but when my son is big enough to ride a full sized bike, I'm considering putting him on my 300. Mostly because it's just a dream to ride, and ride fast so easily. He's on a DRZ 110 right now, and only weighs 59 pounds, so I'm probably looking a little too far in the future, but I really don't understand the notion to put young skilled riders on bikes that demand so much attention from the pilot. Granted, a 200 almost rides itself compared to a 125, but you can ride a 300 in a tall gear, at low rpm and really haul the mail. I've had all three sizes, and loved all of them.
As far as the 200 is concerned, what makes it better than the KTM is nothing more than the perfect Gas Gas chassis. The KTM is a great bike with a great motor, and SCARY geometry. Ever since KTM went to the new 125 in '98, that small chassis has been an abortion. The big KTM's just don't have that problem, and work great for me, but the little ones just don't work for me at anything above a casual pace.