These socks consist of a nylon jersey inner and outer shell, with neoprene sandwiched between. The neoprene has small holes punched in it for breathability. The nylon inner shell wicks moisture towards these holes where it can evaporate. Liquid moisture simply drains out. Of course, liquid moisture also drains in, so the socks aren't nearly as warm as non-breathable neoprene. But once my legs and feet are warmed up, I have no problems walking around in slush at 30F with these socks.
All of my backpacking is done in the warmer months, where 20F is the minimum daytime temperature, and the typical temperature is typically short-sleeve weather. I usually go on long-distance hikes starting each spring and I don't want to pack more than a single pair of footwear. My old approach was to start with waterproof boots, then discard these and buy some shoes or sandals on the road as the temperatures warmed up, but now I just start out with sandals and some neoprene socks in my pack in case of snow conditions.
The neoprene socks are pretty fragile, so if I'm expecting a lot of cold weather, I'll pack several pairs to last me until the warm weather arrives. So far though, a single pair has been adequate per hiking season and I just discard the extras when warm weather arrives.
I should not that I'm quite comfortable walking with sandals and no socks at 40F. For most people, this may take some mental adjustment. I don't think any major physical adjustment is necessary, given that our ancestors routinely walked barefoot at these temperatures and lower. In cool weather, I notice that I typically bundle up in my torso region and wear mittens even when everyone else is barehanded, probably because I'm compensating for the heat lost through bare feet in sandals.
It seems campmor.com no longer sells these socks. They were made by Seirus. I see them in the Seirus.com catalog, but I don't know any reseller who has them in stock. Lucky I still have 3 pair left. I guess I'll have to be careful with these remaining pairs...
As for the Seirus storm socks, these have a W/B liner. When used with sandals, the socks soon develop holes. Water get in these, but then can't get out, so these socks are worthless to me. The breathable neoprene socks don't have this problem because they have little holes arlready punched in the neoprene. All the good products disappear and are replaced by sh*t.