In reference to the grease used on the slide rails and barrel.....if the gun is carried the way it should be, in your pocket, the heat from your body is sufficient enough not to have that be an issue.
I believe that to be true, IF the pistol were always carried on the body. However, in many states (mine included), there are numerous "carry excluded zones" where you simply can't take a pistol. My employer also does not allow handguns on the premises.
As a result, I often have to leave my carry pistol locked in a lockbox in my vehicle. I don't like the idea that Superlube can get tacky enough when cold (and here in Michigan, it can get quite cold). I fear that I'll leave the pistol in a cold car for hours, then enter the vehicle, retrieve my pistol, and find I need it before its had time to warm up sufficiently.
There are also times in the winter when I'm wearing a large parka-style coat, and want to carry a pistol in my coat pocket (where it is much more accessible than under the coat in a pants pocket or holster). Most coats I've owned do not have the pockets very well insulated - the insulation is between the pockets and the wearer. In such cases, I can easily see my pocket pistol chilled to below freezing on a cold winter day.
Superlube may be fine for summer use, but in my (admittedly limited) experience with it, I have serious concerns about using it in cold-weather situations. I believe I'll be sticking to TW-25B (though I may run some tests first to see if one or the other matters much for a 50-round reliability test).