Must Have
I had a North Face version of these pants and they were my go-to pants for ten years. On their own for nordic skiing and hiking, under goretex pants for ski touring and mountaineering, as a first layer under fleece for the really cold stuff, they were the most versatile article of clothing I had. It took a while to find a replacement but I have in the Marmot Power Stretch Pants, and the Marmot version is even better. Much better. These pants are warm, breathable and have so much stretch that they'll never bind no matter what the activity. The outer face of the fleece lets any second layer worn on top of it slide easily over it with no binding at all, which is a great feature. I wear these pants under Marmot soft shell pants when I'm telemarking and when I get into my turn there's not one iota of of resistance. These pants are inexpensive, light and pack up small. If I'm not wearing them, they'll be in my pack.

Comfortable and practical. A must.
Wear them with an outer layer for skiing/boarding or other snow sports. Wear them alone to hike/run. Ordering another pair.

Great for winter running!
I just tried these stretch pants for the first time the other day. The temperature outside was 22 degrees, but my legs were perfectly warm throughout my hour long run even though these pants were the only layer I was wearing. They are incredibly thin and light - highly recommended!

A cold weather must
I am Marmot fanatic and am always impressed with their products. So I just added the Marmot Power Stretch Pants to the Collection. And again, I am amazed. They are a great base layer, comfortable, and simply a must to have.

Great layering option.
I bought these to use as a insulating layer, which they do great without adding bulk. I can use them as my only layer under my shell for warmer days but still have room for fleece when it's colder. They seem to run on the small size. I'm 6' 155 and have the medium and they are very snug.