The tram service is very fast! The longest wait was around 6 minutes during slow times when only one tram runs. Even at peak times (nighttime after the shows, New Years Eve, etc) the cars weren't overly crowded.
With well over a dozen trips, I've only seen a piece of trash once (an empty popcorn tub behind a seat).
The little video that plays does get annoying when it constantly loops the same thing constantly ("Zarkana! Mandarin Oriental! Zarkana!").
Watch for the lighted sign with the arrow that points to which tram is arriving next!