In this hobby, a sharp craft knife often comes in handy. Is an off-brand knife any use?

This is the Scrap-tility Knife Set from Dollar Tree (formerly known as Craft Knife Set), which you can find in the craft aisle for $1.25 USD.

What you get in the pack is a sturdy plastic holder, one knife handle, and six different blades. Note that the only thing holding everything in the holder is gravity, and if you're not careful, you will dump blades onto the floor when you open the package.

Rotate the handle to unscrew the top, insert a blade, and rotate the handle the other direction. Above, you can see the knife ready to use.
My initial thoughts? The holder is surprisingly sturdy, but fails to hold anything safely in place. The blades are thin and bendy. The handle holds the blades tightly, actually a bit too tightly when you want to change blades. The blades are sharp, though. Notice there's no safety cap. Don't press too hard, or you'll get a squiggly cut or maybe a bent blade.
It's a cheap knife, so what do you expect? Compare to Walmart prices of about $5.00 USD for individual brand-name knives, and $30 USD for a brand-name knife set (though with three handles and ten blades).