I fifth (or was it sixth) the Schoeller Dryskin Extreme Pants. You can't go wrong with Cloudveil, Mammut, or Marmot. There are quite a few different Schoeller fabrics. For winter use in the Northeast, I think you're best bet is Schoeller Drysking Extreme, preferably with the 3XDRY treatment. I would let the fit be your deciding factor between the different brands. I found the Cloudveil pant to fit extremely well.
The Schoeller Drysking Extreme is a double woven fabric (nylon on the outside, poly on the inside). It will offer significantly more breathability than any bonded softshell (nylon outer fabric bonded to poly inner fabric) because the bonding adhesive reduces permeability. Powershield, Alchemy, Schoeller WB400 fall into the bonded category. These bonded softshell fabrics will be more weather resistant (wind and water), but are not even close from a breathability aspect. The bonded softshells will likely cause you to overheat on the warmer winter days. With the woven softshells, you can always throw your waterproof/breathable garment on to offer more wind resistance if it is especially cold.
In my opinion, the bonded softshells are more appropriate for ice climbing, or other winter activities that might not generate as much body heat as hiking/snowshoeing. They would also be appropriate for the colder hiker.
John