Bought just for the sake of test them, I usually use British extreme cold weather cushioned boot socks as heavy liner, which are quite similar to compare. These merinos are way much more better quality -and the Brits are of very good one- as one can expect from such a dedicated product. The word is 'cushioned', but what distinguish this particular product, apart from the usual outstanding degree of durability and the care in construction for what weak spots are concerned, is the Huge grade of insulation space; I mean they're really thick. I used to overlay different kinds of socks to wear boots properly but these ones leave you no wider choice than a thin inner liner and don't apply to every kind of boot & shoe I wear except wearing no liner or just a thin, summer-type one. Really thick. Also a nice animal to bring around in the house. Not the average, fast-wearing out ones, the quality is top of the range and I wish I've ordered a spare pair because availability had run out. An hint: wear them paired with "1000 miles" double layer british socks and you can hike round-the-world back and forth without a problem.

Bought another round of these in preparation for the winter this year. Not because the old ones wore out, but because I simply wanted more! These socks have been both tremendously warm and tremendously comfortable. I have used them for lounging around, and also for moderate-to-high activity outdoors (hiking, cutting Christmas trees, etc). They have stood up well and served their purpose under both circumstances. Layering them with a thinner merino sock, such as the ones that Varusteleka offers, has been my go-to option during the colder months for some time now.

Very good sock, wish they where a bit longer though like the older versions just for taller boots.