Wow...the best Japanese restaurant in Chiang Mai that I've been to so far.  A nice variety of menu items and the food comes out surprisingly fast for such quality Japanese food (my 5 stars is almost purely for the food!)

Atmosphere: 3.5 stars.  Authentic feel to the interior and staff uniforms.

Service: 4 stars.  Friendly and attentive staff.  There were a lot of people on the floor.

Food: 5+ stars.  Impressive quality and great attention to detail.  We ordered:
- California Roll - very good although they use egg instead of avacado?? Is this unique to Chiang Mai? (we noticed this in other restaurants)
- Beef Steak - so garlicky (yum!), best treatment of beef compared to many other restaurants, even non-Japanese ones...actually got medium rare as ordered!
- Udon Zadu - firm and chewy noodles, not blown out...perhaps fresh udon?
- Salmon Slim - fresh salmon slices,  shaped in a rose...on a bed of ice. That's how to do it!
- Tonkatsu Set - light, crisp, not heavy on the breading, one of the best tonkatsus I've had.

Wish they had A/C and wifi :) but that will not keep me from coming back again and again for a fantastic food experience!