The blade on the cutter I received came loose very easily when cutting medium weight cardboard. Should only be used for lightweight applications where there's not a lot of tension on the blade. I took off the clip for a good pocket knife!As a mechanic, I find myself useing this knife on the daily. Blades are conveniently easy to replace, it has a small lever you push down, and the blade simply slides out. I see in some reviews people complaining about the blade popping out. That happens with mine too(operator error though) I find myself accidentally pushing the lever down so that must be the same case for everyone else. Overall it's a great deal for the price, matter of fact it's the best deal on Amazon right now. Two for 10$, plus nice qualityI found that the red & green part of the handle is some sort of very very lightweight aluminum. It seemed very fragile. But it did provide its purpose for work for 1 day & I believe with the right kinda care it should continue 2 hold up long enough. The Additional 10 blades is definitely nice 2 have.I think these are a good value. Seem well made, but I've only used them a few times. No problem with the blades slipping or coming loose as some people had. oI was practising changing the blades and one was in so tight I had to use pliers to remove it.I find that when I use this knife, it has a design flaw. there is a spring loaded pin to release the blade and it is too close to the handle. when I use this knife for breaking down boxes, i often find the blade inside the box that I just cut. The pin is too close, or too sensitive, and comes out of knife too easily when in use. I do like the sleek design, however, the blade release is flawed. I am going to try to cut it off on the left side flush to the base, hopefully this will stop the blade from coming out so easily.Pros. Great quality,nice and solid.Cons. Too weak when folded,opens easily inside your pocket.Great for cutting boxes at work and around the house. The blades are really sharp.Not bad for the price, but the not the most sturdy knives ever built. But nearly a year later, I'm still using one of them, while keeping the other at hand as a backup.Works alright but the blade likes to come out when cutting cardboard