We went to Ginseng 3 on 5/24/13 during our last quick getaway to Las Vegas. It was late and we were craving sushi. When in Vegas, I normally go to the place in the Cosmopolitan Casino, however we were looking for something closer and less expensive.
Ginseng 3 is located on the strip, on the 5th floor of the Quad (the former Imperial Palace). It isn't anything fancy, wasn't busy, we were seated quickly and was less expensive compared to any other sushi restaurant I have been to in Las Vegas.
I had order the spicy tuna roll which was about $12 (super spicy), the eel roll which was about $12-$13 and a glass of orange juice which was $4. Overall the service was mediocre as they didn't check on us much, if at all and the food was tasty but by no means would I say excellent.
If you want mediocre, less expensive sushi for the Vegas area, I would recommend checking out Ginseng 3 in the Quad casino.