I picked up both the IMP22 and IMP22L (large) for almost nothing off of eBay. $6 for the small one, $9 for the large, both brand new. I have a Case large sodbuster and I've played with the small ones, and the Schrades are not bad.
Schrade Pros: Thicker blade, comes to a finer point, stronger backspring, nice logo, very nice handles. DIRT FRIGGIN CHEAP
Schrade Cons: Finer point - the Case is more sodbustery, and if the shape is important the Case has it perfect. The Schrade's opening and closing action is not smooth, feels like there is a tiny bit of grit in the pivot on both the small and large Schrade, even after an oiling. That might work itself out over time.
The Case's backspring is rather weak compared to the Schrade. It's a lot smoother to open and close, however. The Case has a quality feel to it when opening and closing that the Schrade lacks. It feels slightly rough. However, once open the Schrade resists closing much more strongly, and the balance of the open knife in the hand is almost identical. In all honesty, the rough feeling opening and closing is really minor, and may be all due to the stronger backspring. The Scrhade is slightly thicker, with less variation in the scales from knife to knife. The Case's handles are polished and smooth and feel better in the hand, but there is a lot more variation in the handles. My Case has an area by the center rivet where the polisher was left on the knife too long, and it makes the handles asymmetrical in that area. Schrade handles are slightly matte, and my brand new knife had marks on it. Nothing major, but if you reflect some light off the handles there are visible marks. Likely from manufacturing, dumped in a bin, then sorted and boxed? Not sure, but there are minor marks.The Schrade has a half stop, which is nice. The case does not.
The Schrade blade is ridonkulously sharp. Receipt paper doesn't stand a chance. It's really, really good out of the box.
Overall... well, the large case can be had for $30 or so. More for the CV blade (like I have), or for rarer colors (like the tomato red I have). The Schrade can be had for $9 for the large one, $6 for the small. The case operates more smoothly. Both are constructed very well, of good materials and finishes. Both come very sharp. The half stop and the extra strong backspring of the Schrade might be worth more to some people than the smoothness and good feel of the Case, especially on a knife that sees a lot of use. It's a crapshoot as to which is better because of that.
But the schrade is defintiely cheaper. And there's a glut of them on the market right now. I've been stockpiling them for xmas gifts.
Charles.