If you only have one knife, do not make it this one. For all the reasons bofh listed, this is inappropriate as your only knife, your only flash light, etc. I'm not sure it really makes sense to have only one of anything.
That said, for ten bucks, this is a useful tool that can be a good addition to what you have already, or a starting place for buying what else you need. Amazon lists it for $52. At that price it's a ripoff.
Fightfast has some interesting products, and sometimes you can get them for a good price. Do not fall for the high anxiety sales pitches --> "We only have 100 of these, hurry order now before we are forced to stop offering them at the low, low price of, the government doesn't want YOU to know."
As long as you don't believe the hype, and don't expect to get the secrets of the universe for ten dollars, both company and product are fair.
