We have been watching this product with bated breath! We are always striving to make our excursions guests' experience the best possible, and were very excited about this innovative product. Waiting for reviews has been nerve wracking, so it was just great to have one of our guests use her own Easybreath mask at the snorkel site and get her opinion.
Overall, she said that wearing the mask was a very enjoyable experience and that it worked well. Her two comments against the mask were (a) harder to keep clean than the "older" mask and (b) perfect for surface snorkelling, but if you want to go deeper, you are unable to hold your nose to equalise the pressure in your ears.
Obviously this is just one review, but it would appear that it is a great product for beginner snorkelers or those who just cannot adapt breathing through the mouth alone. For those who are more confident swimmers and who prefer not to just stay at the surface, this may not be the mask for you.
We will keep you posted if we get any other reviews!