Sharpmaker sticks are basically aluminum oxide bonded in ceramic. AlO is nine point something on the Mohs hardness scale. Steel, no matter how hard you get it, will not get above seven, so no steel should be able to resist your Sharpmaker.
HOWEVER, steel is not an element, it's a compound. Cheap stainless at least has chromium, iron and carbon (the three basic components of "stainless" steel). These elements do not simply merge together, they get electrically bonded into certain structures -- the shape and configuration of which depends a great deal on the heat treating, grain structure, whether it's hammer forged, etc.
Some of these structural configurations can be quite haphazard and weak; others are very neat and compact. Take the difference between a pencil lead and a diamond. Both are pure carbon, but one is WAY harder than the other. The difference is in the structural relationship of the atoms. Diamond uses a compact tetrahedron structure, which is so strongly bonded that you can't force them apart simply by rubbing other compounds against them. Conversely, they hold together so well that if you rub a steel with them, they'll push those steel structures out of the way like they were a house of cards. That's hardness.
Now, on to steel compounds. Like graphite vs. diamond, there are different ways for steel to form relationships between the various component elements. Hence words like "pearlite", "martensite", etc. These describe structural properties of the steel, which relate also to its grain structure (steel compounds into small "grains" of these molecular structures). [Note, I'm only halfway sure about this, since I'm a bit new to metallurgy].
Not all of the steel will be homogenous, either. Some of the chromium will be bonded to the carbon, for example, but some of the chromium will be "free", and not bonded to anything. This leaves it chemically available to oxygen, which will lead to the formation of a chromium oxide barrier on the surface of the steel, providing a rust protecting layer that prevents oxygen from bonding with the iron atoms.
Likewise, many of the other elements within the steel will also bond with the carbon, forming "carbides". Carbide are extremely hard. Silicon carbide is harder than even aluminum oxide (the compound in your Sharpmaker sticks), so that if an SiC molecule has risen up to the surface of your blade, the Sharpmaker stick will not be able to wear it down, only push it around. This is in principal not a really big issue, though. For steels where this happens more frequently (such as crucible metallurgy steels, like 440V), a diamond hone will take care of those pesky SiC residuals.
Anyway, nobody I know ever wants to hear about this stuff, so I thought I'd take a chance and post an amalgam of what I've learned from the Net. The long and short is that if you have a cheap blade, and you sharpen it every day, it will probably cut fairly well. But it may chip if it's not tough enough, and will bend easily if it's not hard enough. A good blade steel with do neither under most circumstances, giving you that "gliding through the material" feeling that a good sharp blade should.
To others, please correct my errors. I'm eager to know myself.
