This tram is rediculously useful, especially when you have family in town and they are staying at Excalibur. This tram actually connects the Excalibur, the Luxor, and the Mandalay Bay.
The tram runs on frequent intervels all day and is a welcome reprieve from all the walking up and down the strip and "playing tourist". There is usually a crowd, but I've never felt TOO crowded in there. Plus the trip is so brief, I'm sure it would be quite tolerable for most people.
The tram itsself has always been reasonably clean when I have used it and air conditioned(awesome in the summertime)..and best of all ...its FREE! Enjoy! Not that many things left that are 100% free in this town!