In a desperate effort to find something to acquire and put in the toy cupboard never to use again, I recently purchased a Kershaw RBK. Being an essentially idle individual I like the idea of a knife that never goes blunt (as one simply replaces the blade) and started looking into the cheapest way of doing this. Fairly quickly I found Havalon knives but decided that they were far too expensive for something which simply allows a scalpel blade to be folded. So after about six months looking and many hours on the net I found the above and saved myself about £10. A tremendous sense of achievement, but a total waste of time.
Anyhow for those looking at a similar thing I tried it on a Red at the weekend and my observations are that whilst it is scarily sharp (as you may imagine) you may go through blades at a rate of knots. The blades seem to take no twisting movement at all before breaking. I broke two on my first animal.