Sorry Zak, I thought you were looking to the Block as a replacement for your current target.
Which model Block do you have? How long have you had it?
The center of mine has softened a bit over time but I haven't shot thru it yet. I tend to spread the shots around a bit. One at each spot or I place a small sticker or piece of paper in an unused section and shoot at that.
The only problem with shooting the edges is that the target tends to spin at impact.

I'd recommend you try a Morrell bag target.......let it hand freely on a frame. You can make a very cheap frame out of PVC pipe. They last a very long time, and like I said you can replace the cover when you have it worn out. Just spin it around and shoot at both sides evenly.