We used Lyft a couple of times when we first arrived in Las Vegas and it was fine. Then we tried to get a ride from the Rio and got screwed. Supposedly the driver couldn't find us even though we were sitting in an area designated RIDE SHARE PICKUP at the back of the casino (they have about 25 seats there for waiting). They allegedly called which I did not receive and then charged us $5 because we "cancelled."
We used Uber the rest of our trip and had no problems. We did not use Lyft again and I don't think I will in the future