I agree with Jon--the Monkey Man, under a windproof shell is probably the better insulator of the two. It can provide some SERIOUS warmth in that configuration. The Compressor is better as a stand alone insulator in breezy conditions, but the reason they call it a "Compressor" is because it is meant to be a very light and packable layer of insulation you can pop out of your bag when you need it and forget it is there when you don't. It's warmth is comparable to a TNF Denali fleece jacket, with better windproofing.

Both Jackets insulate very well. The Compressor Jacket insulates better when worn on it's own due to the fact that it is more windproof than the Monkey Man/Woman. When the Monkey Jacket is worn under a shell that blocks the wind... it is extremely warm. The Monkey Jackets are made with High Loft Thermal Pro Fleece from Polartec. The Compressor Jackets are insulated with 120grams of Primaloft PL 1 insulation. Hope this helps!

This will for sure. The Monkey Man is more of a casual fleece than a serious lightweight jacket.