The link in post #1. Text is in Japanese, it says that these are factory sample products.
They are also pretty damn expensive too. I got them on pre-order discount, and even then I'm finding it pretty rich.And as you said, they don't seem all _that_ different from their G1 counterparts. I initially wasn't going to get these... then I saw them pop up for preorder discount on Amazon JP and thought, "Ah screw it"...
I caved... but I can understand if others are still hesitant on getting these toys.