I`ve probably been here several times already and they never fail to disappoint. Yamamoto is honestly never my first choice when it comes to AYCE. I would choose Matsuda or Ten Ichi. Yamamoto's fish is average at most and their food is decent. Sometimes it comes cold... hello? grilled?
I went once for lunch hoping that I could get AYCE because when I looked online it said that lunch was from 11:30am to 4:30pm. When we got there (it was probably 3pm) we were told that if we wanted to have AYCE, it would be dinner price. We then looked at the AYCE menu and realized that it did say until 3pm. I went home to check online and if you click on their "PDF" of their menu you will see it.
They do offer bentos for lunch which are REALLY CHEAP! totally worth going for. Their fish is probably just what they use for AYCE but it isn't bad. All their bentos are under $10 which is great. I ordered 2 because I was starving ! hehe..
They have pretty much kept most of the interior from the previous restaurant "Mongolian" so there isn't much to say about the decor.