I went there for breakfast twice during my stay in Chiang Mai and had two pretty different experiences.
The choice is huge and I especially loved their Tempeh-Avocado-Sandwiches and take-away sweets, such as vegan brownies, muffins and cookies. The food is good in general, but nothing exceptionally great. The banana oatmeal I had during my second visit was pretty disappointing though.
The place is usually quiet crowded with backpackers, which unfortunately can be pretty loud and stressful sometimes, even though their outside seating in the garden is beautiful! I think this is also a reason why the service seems to be a little overstrained and confused at times. They still manage to serve their food very quickly though.
They even have a little shop area where you can buy organic items, such as soap, incense and other souvenirs, which are mostly produced regionally.
Overall I think there are better breakfast places nearby, but this probably has the biggest variety.
Updated from previous review on Sunday June 14, 2015
Cons: confused service, highly frequented