OLFA9mm Stainless-Steel Utility Knife (SVR-2) - Multi-Purpose Retractable Precision Knife w/Stainless-Steel Snap-Off Blade, Replacement Blades: Any OLFA 9mm Blade

Little bit of background... I do papercutting as an artform. In day-to-day life, I'm not very comfortable with scissors -- knives just work better for my general purpose cutting tasks. My standard go-to blade for light duty general tasks (opening packages, letters, cutting thread, cutting cable ties, etc.) and for my detailed paper cutting has been a #3 scalpel with a #11 blade. I greatly prefer carbon steel over stainless. I gave up on X-Acto blades long ago.I had always been aware of snap-off blade systems, and I had always trusted Olfa blades, having good experiences with their rotary cutters. Recently, I impulsively picked up the SVR-1 (not this knife, give me a second here) locally for full retail price. I was immediately impressed with the build quality -- the body is sturdy, the plastic part seemed unlikely to fail, the whole thing just felt exactly as minimal and exactly as engineered as it needed to be. The SVR-1 and the SVR-2 both come with stainless steel blades, so I checked Amazon to see if carbon steel blades were available. When I went to order some, I then also looked into this product, the SVR-2 with a blade lock. So, now I have both.The SVR-1 has no lock to speak of. They call it a slide lock, and yes the blade clicks into place, but enough pressure on the blade (a moderate amount) will send the blade back into the carrier. The lock on the SVR-2 seems like wizardry at first. You slide the blade into and out of place just as on the SVR-1, with no additional step. The blade follows a step behind, springily, like a caterpillar walks almost. Hard to explain, but the point is, you just slide the blade as you want, but no amount of pressure on the blade itself will send it back into the carrier. Amazing. I definitely recommend this one over the SVR-1, with one caveat -- the plastic bit is the lock mechanism, and it seems far more likely to fail than the simple piece on the SVR-1. When/if this will actually happen, I don't know. But it is a more complicated piece. Otherwise, it's the same sturdy stainless construction, the same easy load/use, the same useful and unobtrusive clip/blade breaker.So, what about the blades? For fine detail work, I still think the #11 scalpel blade will be better. But that's not always necessary, and when it's not, I think I'll be grabbing the Olfa. The stainless blades that came with both knives were typical stainless -- relatively soft, dulling more quickly than necessary. The carbon steel blades are amazing. Cannot stress what a difference they make. For day-to-day light duty utility work, they have already proven themselves. Being holiday-time, there have been a lot of packages coming in and going out, a lot of things to open, and this knife has been with me the whole way. When the blade dulls, breaking off a new tip using the clip is simple. Tips don't feel like they'll break off accidentally. This has been on my mind, though. In my paper-cutting, I often cut through many layers at once, and I often apply far more pressure than I should. I have broken scalpel blades. One shot up to my eye. I guess I blinked in time, my eye came out unharmed, but it sure didn't make me feel great. I'm willing to bet that the more controlled break, if it were to happen, on these breakaway blades would be more predictable. I don't really have any evidence to back that up, it's just a thing that's been on my mind.So, in summary, great design. Engineered/designed just the right amount. The stock blades are probably fine for a lot of day-to-day uses, but the carbon steel blades are not prohibitively expensive and are just wonderful. I really love this knife, and am probably going to replace the utility knife in my toolbag with one of Olfa's 18 or 25 mm snappers.

I bought this knife to use as a marking knife in woodworking (knives give a finer, clearer line than pencils). A marking knife needs to be very sharp, but very handy and safe, because it is in and out of your hand quite a lot. I have tried all sorts of other marking knives, including the handle-less Japanese style. (Once I nearly stabbed myself in the foot when I knocked one off a work table. It would have gone right through my foot, I am sure.) Snap-off knives are superior to all of those. The blade is thin enough to cut deeply, and since the blade is sharpened on the long edge instead of the bevel edge (like Japanese marking knives are), it is easier to bear down while making a cut. The blade retracts, making the knife pocketable. The blade also locks, making it safe to bear down on. Moving the blade in and out is fast and fluid, making it easy to use. Lastly the blade is always sharp, since you can easily snap off a dull section and expose a sharp new point.For years I used cheap plastic snap-off knives, but I always wanted a nicer, more durable version. Those plastic housings can break fairly easily, and the locking mechanism is flimsy. And now I have found it.As others have pointed out, the knife is quite slender, though it is slightly heavier than it might appear, being made of stainless steel. It fits nicely in a shirt pocket. The clip is springy and appears sturdy, and pops off to act as a blade snapper. Nifty!This particular model is auto-locking, meaning that the blade will not move when pressure is applied until you actually move the slider forward or back. It is very easy and fluid to use. Unlike another reviewer, I haven't had a problem with moving the slider unintentionally, but that could possibly be a problem when a blade is nearly used up and the slider is out near the tip of the knife. In any case, I hold it with my index finger extended along the top of the knife, so the tip of the blade is almost under my fingertip. It cuts where I point, in other words. This gives me a lot of control and accuracy, and feels very natural, and no part of my hand touches the slider.Olfa makes a few other knives that are hard to tell apart, even from the descriptions on their web page. The slightly cheaper SVR-1 does not lock automatically. To lock the blade you move the slider backwards just a bit (those cheap plastic ones work the same way.) To me that is a somewhat less safe option. The SAC-1 is very similar, but its blades come to a sharper point, making it more suitable for cutting stencils and other exacting work. It could probably replace those ubiquitous Exacto #11 blades, actually.Lastly, there are three different types of replacement blades: stainless steel, carbon steel, and "Ultrasharp". I recommend the carbon steel unless you work in a wet environment. They are cheaper, stronger and stay sharp longer. Just wipe it with mineral oil or tool sealant like Top-cote.