Gear Review: Minus33 Merino Wool & Wool v. Down v. Synthetic

After talking with Minus33 a few times about their products, I ended up with a Merino Wool Kodiak Expedition Full Zip Hoody and a set of their Merino Wool Day Hiker Socks. Here is a link to the review I wrote:

After testing the hoody and being very impressed with it, I became interested in the possibility of using merino wool as my primary insulation layer. I am moving to New England, where it is wet and humid. Despite being much heavier than down, I like the idea of merino because it still insulates when wet and sweat does not degrade it.

What are your thoughts on Wool v. Down v. Systhetics as an insulation layer? Other than weight and "compressibility," are their other reasons to not use merino?