STAY AWAY!!. I can not emphasize this enough. The money you think you will save with a prepaid round-trip ticket will be quickly erased from the cab ride back to the airport because they were either late or DID NOT SHOW UP AT ALL.
Like the others, we purchased our RT fare online. When we arrived at the airport, we had to wait 30+ minutes for our shuttle. During this time, we stood at the front of the line breathing in all the exhaust from the other idling diesel buses. When the line turned into a large group of about ~40+ ppl, it caught the attention of one driver from another route and he was considerate enought to take us. However, he started loading people from the back of the line who had just gotten in line. It was very apparent that we were at the front and we had to speak up before he let us on. He was only able to load about half of the crowd. Once on board, we got to our hotel (MGM Grand) in just a few minutes.
Coming back however was a nightmare. First off, you have to call to schedule a pick-up which we started calling at 5 PM. Good luck getting through the first time as we kept getting "all circuits are busy, please try your call again later" (don't believe me, call 702-739-5700). We had to keep trying for nearly 10 minutes before even getting the answer system to pick-up. Once it did, it took another 12 minutes of hold time before we got an operator. They asked for our airline, flight number ,and take off time (not really sure why it was important). They only gave us 2 pick-up times: either 6:30 or 7:30 PM (we asked for 7 PM). We went with the earlier time just in case they were late. Turned out to be a good thing.
6:30 came and went. We started calling again at 6:40 and got the same busy phone circuit and wait time once connected. When we got the dispatcher and informed that they were a no-show, the girl on the phone hung up on us.
We saw a Gray Line shuttle dropping off passengers at the hotel main lobby (airport shuttle pick-up is at a different location) and ran over to ask if we can go with them. The driver had a load of people and MGM was the first stop, but he said he would call the office or swing by afterwards if he couldn't get through.
It's now 7:15 and still no bus insight. Unable to get through to the dispatcher, we decide to catch a taxi and dispute the credit card charge later. We get in line for the taxi queue and just as we get up to the front of the line, the shuttle arrives. The time now is 7:30. It turned out to be the same driver from earlier. He informed us that dispatch never received a call for a pick-up request. Um... whatever.
The driver was nice however still does not make up for the aggravation and the wasted time that we had to go through.
STAY AWAY and NEVER AGAIN!!!!!