Overall, I applaud Oakley's attempt at a higher end mask with features designed to reduce some of the issues other masks face. This spirit of innovation is what makes Oakley so great. But with Oakey, sometimes they don't get it right on the first try and require a few attempts to get it proper.
I think the mask will be great for a good portion of the population, but it doesn't work for me for a few reasons:
Fit: The MSK3 needs to fit properly to leverage all of its design features (such as reduced fogging through use of gaskets), but it's so small that it doesn't fit me correctly. It really isn't a one-size-fits-all mask. For comparable products with the same style and structure, the MSK3 would translate into a MD/LG size for Under Armour masks. I suspect the average male would need a LG/XL for a proper fit, which is what I usually wear with UA.
Removable filter: The MSK3 is one of the easiest masks to breathe through, but I think it's mostly due to design flaw than anything else. The removable filters attach via Velcro on the left and right sides of the MSK3. There is nothing attaching the filter to the base mask on the top or bottom. When you inhale, the filter will pull towards your face, but that exposes the top portion of the mask to air. You breathe easier since fresh air gets through the gaps without going through the filter, so it's not very functional as a protective mask.
Straps: I love the fact that you can adjust the strap length, but I don't particularly find it comfortable or that it yields a proper fit for me.
Contouring wire: On most medical masks or comparable masks, there is an adjustable wire at the top edge where you can contour it to your face. The MSK3 doesn't have a wire running the length; instead, the wire is located exclusively in the nose area, both in the base mask and the filter. The idea is that you can adjust for your nose, but the rubber gasket running at the top of the mask will contour to your face so a wire isn't required. I get the concept but I would've liked a wire instead of hoping the gasket would provide a proper seal. Perhaps if the mask was a larger size it would've worked better.
As an Oakley fan, I'm glad they put something like this out and am glad I bought a couple. If I wasn't a fan however, I'd not have been impressed with the fit and function of a $60 mask compared to $30 alternatives.
Thanks from me as well Oak! You must be a mind reader because I was going to o.com on and off throughout the day yesterday staring at the mask, reading the info, thinking about it, debating what to do. Your feedback has helped me lean towards a decision.