I have a variety of wool garments. I find wool superior to synthetics as it is slightly more thermally efficient when wet, gives off heat when drying, and is fire retardant. One drawback of wool is the unpleasant scratchy sensation experienced when wool is worn next to the skin.
Terramar states that Thermawool is "soft next to the skin." I have the box next to me as I write this review and that is a verbatim quotation...
This garment is listed as a middleweight sweater, but is so thin that I wear it as my first layer under the torso of my farmer John wetsuit.
The sweater is much less scratchy than many sweaters, but it is somewhat irritating. It isn't so bad that I refuse to wear it, but I only wear it next to my skin in extremely cold weather when I favor wool over synthetics.
On a positive note, the garment is well made. Taking a page from modern, synthetic performance garments, the sweater has specially formed, articulating panels under the arms.
Whether I wear a wool Thermawool sweater or a synthetic layer next to my skin, I add a second Thermawool sweater over my wetsuit. Depending on conditions, I add another Thermawool sweater-one size larger and with the sleeves cut off just above the elbows beneath my paddling jacket.
If Terramar hadn't included the bit about next to skin comfort, I would have rated this garment a 10.
Field note: Although synthetic fabrics retain a good deal of heat when wet, wool retains 80 percent when wet. This performance is unequalled by present synthetics. Keep in mind that the trapped layer of warm air between each layer of your clothing will immediately be lost if you take a swim. ONLY the heat retained by the garment fabric will remain to keep you from hypothermia. I kayak in subfreezing temperatures on water below 50 degrees. In such conditions, I use the highest performing fabrics I can. I am not disparaging synthetics in general, as I do use them.
Thermawool sweater: Recommended