We did not know about this place before we walked through the Mandalay Bay shops area on our way to the casino from the hotel next door. Walking past it, our eyes caught the words 'vegan menue', so we walked in.
We shared the Romelia's salad and a Meatless Meatball pizza. The salad was very nice, fresh and delicious, and we also liked the dressing (maybe a little too much dressing for my taste though). The pizza was also really good, and the faux meatballs were pleasently spiced. I also found the food to be reasonably priced (though not inexpensive).
We had to wait quite a bit for our food (maybe 40 minutes), but the staff was really apologetic and friendly, and we ended up getting our drinks (four beers) for free as compensation. Unfortunately we were too stuffed to try the desserts (the menue says they have Chocolate Cake, New York style cheesecake, and Zeppoli).
I would definitely recommend this place. I did not at all expect to find a vegan menue in one of the hotel restaurants, and was pleasently surprised by the tasty food.
Cons: a bit noisy