Figure 9 vs knot

The odd-looking device is a "Figure 9" designed to help tighten a length of rope. Tying a length of rope tightly is very handy, especially when going camping.

The knot on the bottom right is a taut-line hitch, a very useful knot that that the Figure 9 is most likely to replace.

I've read a few reviews on the Figure 9 saying how great it is if you're not a "knot person." I kept seeing it at REI. So, for two bucks, I got one to try it out. It seems okay. I don't like that the teeth on it will fray your rope if you're not careful. But what I really think is, it's not that hard to learn to tie a proper knot.