You can see in that picture that the pins are not the same. That is definatly going to mess with the #3 jet if those holes get partially covered by a pin. That will hurt flow and performance some.
Here are the pics of the 300 pin base on the one I have. As you can see the pins still very but I don't think they very as badly as Robo's. Next time I take the block apart I will look more carefully to see how the holes on the #3 jet line up. Last time I looked it did look like there was some overlap. I just about got my bench replumed and will run the block again with the new plumbing and silver TIM compound I switched to. Might not be all that usefull though if the retail blocks are now slightly different/improved.