I've been told that Vegas isn't really known for it's Greek food. Milos in the Cosmo is good, but I guess the person who told me this was referring to Gyros and the low-end Greek foods.
Yanni's was good! My brother, his wife and I were on our way home from the grocery store and Target (a very wild Vegas evening, right?) and we called in an order. Picked it up on the way home.
What stood out to me was the Tzatziki sauce. They make sure you go home with a lot of it, too. Slathered that stuff all over my Gyro and french fries. Yum! The Gyro was HUGE, too, and there was no way I could eat it all. Two people could easily split one with a side order of feta fries.
Good enough for me, but hey, I'm no expert on Greek eats!