This is the Cadillac of pens. If you want the best pen technology that ever existed, this is it. Why carry a big, fat sack of pens when you could just hold one? One mighty pen, strong enough for any situation. For kids, this works well because kids can write in any color. As you grow older your options for writing diminish down to blue or black. Most legal forms won't accept your beautiful orange and purple writing. It's not fair, but it is the way it is.
The worst thing about these pens is when they would jam. It has a million springs in it. It's going to jam at some point. It's just a matter of one. Probably when you try to do the pen's final form: every single color out at once.