I live in NY and bicycle from Brooklyn to midtown NYC to work most days.  I have an Under Armour balaclava (or ninja mask as my kids call it) which keeps my head and neck warm but it was very restrictive to my breathing when over my nose and mouth.  Couple this with a feeling of claustrophobia due to the compression fit of the mask and you can imagine how uncomfortable it was.  Needless to say, I kept my face exposed all of the time.  When it got down into the low teens outside I decided that I needed some extra protection for my face.

I ordered the Seirus Innovation mask figuring that the open nose and "perforated" mouth would help.  I have to say, I am VERY pleased with how this mask performs.  When the temp hit the low teens, the wind chill was 1 degree according to the weatherman.  With me hitting an average of about 15 mph on the bike ride, the wind chill was actually -9 degrees!  This mask kept me toasty for the 50 minute ride to work.

In addition, the fit is great.  I ride with the balaclava as well as a set of Aftershox headphones which go behind the head.  I initially tried the Large but it was very tight so I went for the XL.  The mask fits perfectly.  When I ride I am able to breath freely through the nose and don't have that claustrophobic feeling anymore.

One thing you should know, if you wear glasses you MUST breath out of your mouth when riding.  I wear glasses and, when exhaling through the nose, it causes my glasses to fog up.  This is not unique to this mask as the same thing happens with the balaclava.  Just something those of us with less than perfect vision have to deal with.

Overall, I think this is a great buy for anyone who bikes, motorcycles or does any winter sports and wants the extra face protection.