D.N.
I have 2 leapsters and have looked into getting a didj for my kids. I think it is great to be able to plug it to the computer and download-according to the commercials. If you are looking to spend the money for it, Then i would go for the didj. I think it will grow more with your son and it is supposed to teach more as well. My kids think the graphics they have on the didj are "cool".