The blocks finish at 9 or 10 inches (I can't remember right now, and I don't have a ruler handy...), so without sashing it will make a small baby blanket, and with it will make it a bit bigger.
I'm torn. On the one hand, I like the separation of the sashing, but if I sash, WHAT COLOR? On the other hand, it looks pretty cool all smooshed together, and then I don't have to figure out what color to sash in! Heeeeelp!