One word? Outstanding. I bought this piece after making the switch from a synthetic base layer to a merino one. Great move on my part. I wanted to update my mid layer, and decided on the Ignition due in part to the EXP construction. It is incredibly warm, and with the beauty of merino, is not too warm for a mid-layer piece. I’ve also used it as an outer layer piece on cold dry days and it performs amazingly well. This piece is super warm and cozy on the cold days, and super breathable and comfortable on cool days. The long sleeves and thumb loops keep the cold out, as does the form fitting, comfortable, high zipped neck. This was not my first piece of Icebreaker merino and will not be the last. My switch from synthetic to merino continues. Merino simply outperforms any of the thermal synthetics I have used, causing me to rid my closets of all polypro and similar synthetics. It’s all going to be recycled!

Icebreaker continues to make really good stuff. The high neck and thumb loops on this Ignition Zip make a surprisingly large difference in heat retention. Plus, they've managed to make wool into a legitimate wind-stopper. I'm using this layer, together with their 200 and 260 weights, as the only top layers I'm wearing for backcountry climbing and snowboarding up to about 14,000 feet, for temps down to about 20F.

Okay, so I got my husband an Ignition Zip for his birthday and I knew he would never write, but I had to. Unbelievable is all I can say. He wears it as an outer layer touring or snowshoeing, walking the dog even pounding nails all day long. Plus he wears it as a middle layer while riding lifts.