Depends on how much space you want. I'm not sure I agree with the logic of adding a "col-XX-1" in between each one, because you are then defining an entire "column" in between each one.
If you just want "a little spacing" in between each button, I like to add padding to the encompassing row. That way, I can still use all 12 columns, while including a "space" in between each button.
Bootply: http://www.bootply.com/ugeXrxpPvD