It does sit you down, although not as much as I believe most people want compared to the 2010 seat. About a 1/2 inch from what I can tell. As to sitting you back, I don't believe it does this at all based off my seat of the pants feel. The passenger portion of the seat is a little wider and padded much better than the 2010 model. All in all it's a much better seat for me, but I'm not sure it will be for everyone, but for the price it's quite a deal.
I'm not sure what the fixer block is? It's a direct replacement and requires no additional attachments to the seat or bike.
NCBeast, based on previous post by you and some interaction, I would doubt this would be a good solution for your height and leg length, as it does not move you back any from what I can see and I'm not sure how much it could be modified to move you back. I like the seated position so much that I will be moving both the brake and shifter 2" forward with this seat to address any of my leg room concerns.