Maybe the place you bought your Slammer had some old stock still... My dad bought a new Slammer that was a 9 inch like Woodsac's so I know that Mike is making the 9 inch in the new design....
That said.. I love the action on my 9 inch with the 2 hinges as opposed to the 9 inch my dad got with one hinge... I'm sure Mike had a reason for changing the design and I have no doubt it will catch fish.