I have a pair and I actually used a pair in the military back in 1967 over in Germany. I did not wear them often.
The one thing I dislike about them is that they are too heavy of a material. I used to do a lot of mountaineering and winter skiing and snowshoeing and camping. I prefered the US Army dress wool pants AG-44 model. They shed water/snow very well and they are the perfect weight fabric to be warm and comfortable. The problem is that my waist has grown a few inches and the pants are too small now.
Anyway, the M1951 wool pants are well made and a bargain at that price. They are just a bit heavy fabric, too warm perhaps. I bought mine because I can get the waist size that fits and I still search for some AG-44 wool dress uniform pants, have not found any yet in a large enough waist