User blog comment:Jao and jom/Item Idea/@comment-4636093-20121001223630

It gives way too much.

Take a standard person building full AD. They'll usually end up getting about 300-400 AD

That's 150-200 free AP

And on someone building full AP they can usually get between 500 and 700 AP

That's 175 - 245 free AD

On someone with dual scaling like Jax, he could just build full one ot the other and get the benefits of both. I know because I designed an item with an identical effect a few months back. http://leagueoflegends.wikia.com/wiki/User_blog:Krufix/Item_combos.