Whatever anyone does, I don't recommend getting this generic hobby knife set:
I bought one years ago at a woodworking show, from one of those dealers who sells tools from close-outs, bankruptcies, and auctions. I have proper X-Acto brand knives and saws, but I figured I'd use it in my traveling tool kit. Apparently Walmart sells them today. They probably come from the PRC.
The problem I found with these knives is that the clamp, the part that holds the blade under the ferrule, is made of plastic on these generic knives. On X-Actos, this piece is metal. And eventually, the threaded plastic shaft that fits into the handle will snap, leaving the knife useless.
I thought about replacing the clamp with an X-Acto piece, but unfortunately, they aren't threaded the same, so the X-Acto piece won't fit.
The Nr 2 handle, with the red grip, also has a plastic clamp inside, but I've hardly used it, so it hasn't broken yet.
Fortunately, I only spent about seven bucks on it. But it illustrates the lesson that I learned from the Frugal Gourmet, back in the day-"Frugal does not mean you're cheap, it means you don't waste anything. A tool that is more expensive but lasts a long time is a savings compared to buying cheap tools that wear out frequently and have to be replaced frequently." Invest in good tools.