I spent couple days complaining about the selection of "Famous Airplanes of the World" series from Takara. Let's look at it from the other angle. I have just loaded the Series #2 into my web page. You can see more details of this series.
In summary, if you put aside the selection problem, the kit actually is not a bad one. The painting is as good as what you get from Takara. You also need to do some kind of simple assembly and it does create a little bit of fun to me. The molding is good so when you cut the parts out from the sprue, you won't scratch the paint on the body.
The Ar234 is really a special to me as in one "big box" of 12, you normally get one box of special. Unfortunately, it's at the expense of one Ar234. It means you will only get 2 Ar234 in a box of 12. So, some of these Ar234 (kit #11 and #12) actually are as rare as the special planes. (This is my experience so please comment if you get a different mix).
Again, it's not recommended if you want to buy these for your 5 year old kid as the parts are really small.