I spent some time this weekend practicing my firemaking skills. In the process I used my
BCB wire saw for the first time. I was impressed with what a great job it did. I was able to saw through 3"-4" hardwood logs with little effort. This was definitely easier and faster than chopping through the same wood with the
BK&T CU-7 knife. It would be even easier if you mounted the saw to an appropriately sized flexible stick to make a bow saw.
I suspect that over time the sharp "nibs" on the wire saw would get dull, and I don't see how you could re-sharpen it. I suggest that you get 2 or 3 of these saws (they're cheap) so you can train with one and always have a fresh, sharp one in your "for real" kit.