whats better the Montbell Thermawrap or the Mountain Hardwear Compressor? I know the Thermawrap is lighter, which is a big concern for me.

They are both great jackets The compressor is the warmer jacket, also heavier and will not compress down as small. The fabric is a bit tougher/heavier as well, though still very lightweight. The Thermawrap is absolutely featherweight, and it is in my pack or my suitcase every month of the year. Because it takes up no space and weigh next to nothing, I have it with me to take care of sudden drops in temperatures. To me the Thermawrap is a specialized piece for fast-and-light, trek-and-travel, bike tours, 3-season hiking and climbing, and winter layering. I love it. I would grab the Compressor if you need warmth, but also more toughness, more durability, or something that functions better as a casual jacket for everyday cool-to-cold-months wear (the Thermawrap is a bit too shiny to wear around town for my tastes and the fabric is very, very thin and lightweight.) The tradeoff is more weight, more bulk as a layer and more volume in a pack. Hope that helps!

Montbell. Light and warm.