I have used several Mtn. Hardwear products. I first became familiar with them while using the Exposure Parka while on Denali. This is a 2-ply Gore-Tex construction which makes it very heavy, especially for a mountaineering parka, but it took good care of me in 100+ mph winds and temps of -40 degrees F. It even held up to a climbing partner landing on me with his crampons after a rappel. I only needed to perform minor surgery on the parka to repair it. It also did very well in the South American Andes. Again, my biggest complaint with it was that it was very heavy and the outer fabric soaked up a lot of rain if not recently treated with one of those Gore-Tex renewer sprays. This made it almost impracticle in the Cascades as you normally approach with a high liklihood of rain.
From there, I went onto the Ethereal FTX parka. This is a 3-ply Gore-Tex parka. I found the features to be perfect for my needs and I really like the double "Napolean" pockets. I did find, however, that the hood does not fit as well around a helmet as the Exposure. The weight problems and amount of soakage were greatly alleviated with the new addition.
Overall, I would highly recommend Mtn. Hardwear as a great company to buy from. I've had mixed experiences with their customer service department. On one hand, I walked into their place in Berkeley and they gave me a tent fly that someone had returned for a warranty issue. I was only interested in the material so I didn't care about the condition. On the otherhand, I sent in a fleece jacket to have the elastic cuff resewn and it took 3 months to get it back. I'm just glad I had a back-up.
I have used their tents as well and have found them to be on par with the best of the other companies, in relationship to double-walled tents. I am still partial to a Bibler single wall for mountaineering in respect to weight, durability, and performance.