So I've picked three from my collection, all well under £15.
Victorinox Solo - £14
CRKT Edgie - £12
Imperial Schrade Sodbuster - £8
Victorinox Solo is a solid contender, the blade steel Victorinox use is somewhat a mystery, certainly it doesn't appear to be well documented what they use, its certainly a surgical grade stainless steel and I've never had any issues with rust over the years, as well as edge retention from heavy use.
The main pluses of the Victorinox Solo, is consistent quality across their range, a choice of handle materials and its general acceptance by non-knife people who see it as a tool, not as a weapon, which you will get from some of the more "tactical" looking blades such as the first and second gen Lansky World Legal blades.
(pen for idea of size)
The negatives, would be the complete lack of a pocket clip, which admittedly isn't super important with knifes this size, additionally they are quite stiff to open, so even if you buy an after market thumb stud their not easy to open one-handed and with out a thumb stud its impossible to open one-handed, which with me is a massive negative.
Overall a great knife for the money, due to its consistent quality, solid lock-up and edge retention.
CRKT Edgie is an interesting knife for the money, when you first pick one of these up the weight is noticeable for such a small knife and the only thing that lets it down when you first handle it, is the choice of handle material which is a textured plastic. The blade material is a 420J2 Stainless Steel, which really isn't a great blade steel as its a little on the soft side. This is overcome by having an integrated sharpener within the handle, which through use has proven to keep the knife razor sharp.
The pros, besides the low-cost would be the inclusion of the pocket clip and large-ish thumb hole, which allows for one-handed opening. Additionally the chisel ground element on the blade which I thought I'd dislike and sharpener combination actually comes in really useful for basic food prep tasks when out and about.
The negatives, basically come down to the choice of materials, primarily the low-cost blade steel they went with and handle materials. The pocket clip although useful and with great pocket retention, is not deep carry and the top of the knife is clearly visible which I'm not fond of.
Overall for the money it's well worth consideration, and as an EDC blade the legal nature and one-handed opening makes this one of my go to knifes.
Imperial Schrade Sodbuster is a fantastic knife for the money, and is very similar to the Victorinox Solo, both in size, blade thickness and build quality. The choice of materials does make this feel and look like a much more expensive knife, and the use of 400 Stainless Steel for the blade is more than sufficient for the type of everyday tasks you would be using a small pocket knife for. The edge retention and rust resistant properties keeps this little blade going for a considerable amount of time before it needs to be re-sharpened.
The pros, besides the overall appearance and build quality would be the stiffness of lock-up and it comes razor sharp from the manufacturer. It also has a very non-aggressive look which makes it a nice option if you plan on having it out and using it a lot, and don't want to worry people.
The negatives, although the knife was sharp from the manufacturer, I found that the quality of the grind when I've ordered several of them as gifts has not been consistent, with the occasional removal of a little too much material on the blades tip. It also lacks a pocket clip and cannot be opened one-handed without the purchase of a aftermarket thumb stud.
Overall for the money it's worth having one or two of these and the feel of this low-cost option surpasses a lot of the more expensive knives.
Conclusion
If I could only have one I probably go with the CRKT Edgie, for no other reason that the knife can be opened and closed one-handed. The blade material and handle are not an ideal choice but with the inclusion of the integrated sharpener, the downside to the blade material is less of a problem. Even if you're going with an alternative EDC blade, I'd give the CRKT Edgie an honourable mention as a food prep knife when camping.
Other notable cheap legal EDC options such as the non locking Opinel are good, although I found handle finishes to be all over the place and the first and second gen Lansky World Legal, which I didn't like the look of and had some odd comments from people who saw them more as a weapon, then as a tool due to their blade shape.
