I bought 6 pair of Hanes Thermal pants and shirts for the wintertime and working outdoors in cold climates. These work really well and are a great price. The products were delivered in a timely manner, and all sizes and products were correct.
About what you'd expect for thermal underwear at this price point. Not sure what X-Temp means, but it doesn't relate to thickness or any great amount of warmth.
That being said, they fit well out of the box (haven't washed them yet).
If you're layering, these make a decent inner layer for the money.