I came here with 6 of my friends for all-you-can-eat sushi (dinner), which is ~$24/person. It was such a great deal, and I'm pretty sure we all ate more than $24 worth of food each. Our servers were very friendly and fast; we kept placing orders and they kept bringing the food.
I ordered so much nigiri, sashimi, seaweed salad, and miso soup. All of the fish tasted fresh and the nigiri did not have too much rice, unlike other all-you-can-eat places I've been to. I also ordered a roll but I didn't like it very much because it was covered in mayo. In fact, most of the rolls at our table were covered with sauce, so I don't recommend wasting time and stomach space on the sushi rolls.
Definitely try to order two or three things at a time rather than ordering a bunch of food you think you can finish at once because they WILL charge you for unfinished food.
If I'm ever in Vegas again, I will definitely be stopping by Yama Sushi.