(UPDATE: The pair I wore initially have developed more holes along the heel stitching (nearer the ankle now) after only two days wear (worn about 20-hours total). The other two both show weakness along those stitches and although no holes have opened up yet, I'm returning all three pairs. I think they're weak, as far as construction, and too light-weight to be considered a serious winter sports sock.If you live, play, or travel where it is seriously cold, these are not the socks for you unless you have heavily insulated boots or where additional socks. If you chill easily - which I definitely do NOT - you will always want to wear two pair of these or wear them as sock liners under heavier socks. They are that light (Note: They may be too thick to wear two pair without upping the size of your shoe/boot 1/2-size).These socks may work better for you if your calves are smaller than mine, but I've worn Wigwam Over-Calf Socks for 30+ years and NEVER had these problems before. And, the girth of my calves is smaller now, if anything, compared to 30-years ago. I'm returning all three pairs, which I bought just last week. I don't keep equipment I feel is prone to failure.Yes, DISAPPOINTING - I bought several other pairs of socks to "test" for this winter sports season. These Wigwam socks are the ones with which I expected no issues. Yet, these are the only ones going back for failure to perform. A different pair is going back because it's just too small. One more because it's TOO BIG [hard to imagine] and gave the impression there were four pairs in a pack when there was only 1.Aside from that, at 28° F they were warm enough, alone [no lines], in Brooks Glycerin running shoes while moving; after standing basically still on blacktop for 10-minutes, I noticeably started to feel the chill more than I though I should.)Original review:I'm 6'2 with large calves. My feet are size-13 and I wear size-14 in mountain sports and running shoes for extra room in the toe box. I already see that they about are 2" too short to stay up consistently as over-calf socks. Even before trying them on, it was obvious that the foot (from heel-stitching to the toe) was proportionately much longer than than the calf (heel-stitch to opening; fresh from the package, folded at the heel-stitch, their calf is only 3-3/4" longer than the foot). That puts the top on a larger girth of my calf than nearer the knee, which would hold them up better. In my experience, they are simply not tall enough to stay up on legs like mine, over time.They stayed up tonight at my son's Scout meeting (a walking tour of our local PD), but on a weekend hike or day-ski trip, I don't think they would without tape, stickum, or tight insulated underwear helping. They were feeling pretty loose before we left.When we got home from Scouts, I noticed separations forming at the heel-stitching that appeared to be missed stitches. Looking at the others now, it seems all three pairs I bought in this purchase may suffer from that issue. Honestly, they look like what I might expect of a factory-second. I have 20-year old Wigwam boot socks I still wear that haven't done that yet. These were reasonably priced though, so I'll probably keep them. Although, I'll be keeping a close eye on them too.They feel about the same weight as a cotton athletic sock; obviously not as soft, but not too scratchy for wool socks. They are NOT a heavy-weight sock. Sock-liners or 2-pairs would be advisable for all-day jaunts into snow or subfreezing temperatures (with boots). I might use them as a liner/"Base Layer" (maybe with an actual liner underneath) in subzero temps.Overall, they're kind of disappointing given my past experience with Wigwam; still decent socks, just not as heavy, as well-constructed, or as tall as I'd hoped.These are just OK Ski socks. I bought these as a cheap of ski socks when I only had one pair of socks and didn't want to spend 2-3 times as much for a second pair of socks. That was about 4 years ago and while the socks has held up fine for me, I haven't used them much and find them to be inferior to the ore expensive socks. I particularly take issue with the "High Performance" in the name. This are not high performance socks, they're really thick and don't fit very snuggly. I find that while these are fine for using in rental ski boots, this really don't work well in performance fit ski boots, as they're too squishy and keep the boot from fitting properly. If you're just getting into the sport and using rental equipment, these will be fine and they're relatively cheap, but if you have your own ski boots, do yourself a favor and pay a little more for a more performance oriented pair of ski socks. They'll keep your foot from getting blisters and enhance the fit of your boots and generally be worth the extra investment.XL socks have a longer foot, but aren't any longer in the leg. The result for a tall person is that the cuff along the top of the sock digs into their calf. My husband wears size 14 shoes and is a thin-to-average weight adult. We ordered XL socks for him. There was no way that he could have worn these skiing (or even around the house for that matter). The top edge of the sock is designed to sit above the calf, below the knee, with the tight cuff working to keep the sock up. For my husband, the sock did not make it above his calf and instead it dug into the middle of his calf. We will be returning the socks. This is disappointing because I have a couple of these types of socks for myself and they have worked well for me, but why even bother selling the XL size if it won't fit? EuroSocks worked out well for him as an alternative.These are very comfortable socks and I'm generally very pleased with them. It's interesting reading reviews on socks and even gloves where some report their fingers/toes were cold in 30 degree weather while others report being kept warm at below zero. That said, my toes have gotten cold with these socks when temps are in the teens and I'm skiing. My boots are med/low-end boots but new, so perhaps that's important. I think the relatively low wool percentage makes these good for skiing in 20F+ weather but a higher wool percentage sock might serve you better in colder temps.My ski boots have started to pack out. I wanted thick socks to take up the volume. These do the job. And are inexpensive enough to launder in the machine instead of hand washing.Pretty happy with these socks I bought for my son to go skiing. Comfortable and fit well (shoe size 13) - they seem to protect some particular spots that can use the help in a ski boot but no extra bulk or padding. I would say it is a good quality for the price point. I bought 2 paires and the seam on the toes on one of them came undone after first use, it can be fixed but I had nothing to do it while away skiing.The sock seems to be well made and fits well. I ordered a size larger than normal to fit over another pair of socks and this has worked out well for a very cushioned and warm set up. My feet have not gotten moist from perspiration even after long hours outdoors. The only thing I wish was done better would be for a wider elasticized band at the top of the sock. The narrow band is a little overly tight to keep the socks up.Went on a ski trip with the family and bought these for myself. Due to an injury I couldn't ski, but went tubing instead - with normal shoes on. Family members with actual snow boots on were complaining of cold feet, while my feet were nice and toasty. Few days later with the same shoes on I was outside in the snow - without these socks... My feet were cold within minutes. Gotta say, they work!