superlube is a ptfe powder lubricant suspended in various kinds of synthetic hydrocarbon. they have thick hydro, thin hydro, etc, but that's the basic idea. krytox and silicone greases use polymer substrates that are significantly less volatile. the important difference here is that they have higher operating temperatures (ie, they do not vaporize at low specific energies because they are relatively inert polymer matrices), and they do not react with plastics. superlube could very well react with your plastic parts over time, or immediately depending on which formulation you use. i do think there are more inert formulations of superlube, but i don't know enough about it, and the composition is kind of trade secrety. that said, the major characteristic of superlube is that it is the cheapest lubricant with some form of ptfe in it. that is basically it. keep in mind that this is actually the commercial goal of superlube -- to be the cheapest lubricant with ptfe in it. blaster(tm) is the only thing i know of that's cheaper and they only have a very volatile hydrocarbon formulation that's supposed to be a dry thing, but they claim that the hydrocarbon is inert or vaporizes too quickly to degrade plastics.
regardless, i have put a huge amount of time, effort and money into making krytox available for the community because it's superior in every way. krytox has two components: a PFPE oil, which is a completely flourine capped polymer substrate, and very fine ptfe powder that is processed such that it forms a matrix that contains the oil (notice how the formulation of krytox is exactly the opposite of most of these ptfe lubricants, the ptfe contains the oil instead of the other way around). the radio edit is that this allows the surface stiction of the ptfe that everyone else claims to actually happen. tension keeps the ptfe in place, and the ptfe keeps the lubridicity-providing oil in place.
further, PFPE oil can be refined and formulated such that it's one of the most inert compounds in common existence. it is a completely fluorine capped polymer; fluorine capping is valuable because fluorine is extremely volatile (ever mess with hydrofluoric acid? please don't, it's really really nasty stuff) and satisfying all its bonds means that a heck of a lot of bonds have to be broken to expose any molecules of the polymer. this makes for an incredibly inert polymer that _never goes away_. this is great for us, because desoldering a keyboard, opening every switch and lightly brushing friction surfaces is a HUGE PAIN IN THE BEHIND that you definitely do NOT WANT TO DO EVERY MONTH.
also, it's much harder to melt the ptfe in krytox than it is to melt the ptfe in any other ptfe-containing compound. this is quite good because ptfe release formaldehyde when it melts at 260C. notice that once solders between 350C (leaded solders) and 450C (unleaded solders). ventilation is also important if you have any hydrofluoric acid around. nasty nasty stuff.
