Competition in the Las Vegas AYCE (All You Can Eat) scene is fierce, one of the most recent causalities is Sushi On Rainbow on the Westside of Chinatown. It's somewhat hard to standout in such a crowded field. Generally, I like to categorize them in which part of town they are in.
One of my "must go" places have been added in the Southwest section in Las Vegas.
Oyshi Sushi won't have the premium quality sushi, expect the fish to be previously frozen but still is not bad, the rice to fish ratio is more fish than rice, the rolls are not too over sauced, the salmon roe and flying fish eggs to be plentiful.
Customer service is excellent and attentive, they will stop by frequently to check if you want more orders. Several notes:
They charge for green tea, so don't be surprised to tacked on a few more dollars for this. The prices are in line with other AYCE restaurants, just a few dollars above $20 for lunch and around $26 for dinner. Pass on the green tea creme brulee and green tea ice cream, barely any hints of green tea at all.