First, be aware that Metrorail and Metromover are completely different entities. Metrorail is more like a commuter train that runs north and south of downtown Miami for about a 25-mile stretch, as well as out to the Miami airport. You DO have to pay a fare to use Metrorail.
Metromover is more like a small tram that runs much shorter ‘loops’ around the downtown area only. The track is elevated, but not very high. For some time now, Metromover has been running as a free service.
There are two stations where you can transfer between Metrorail and Metromover, otherwise they are two entirely different transportation services. (Note: the Metromover itself does NOT go to the airport without some kind of connection to other transportation).
The Metromover consists of three loops: The Downtown loop, the Brickell loop and the Omni loop.
The downtown loop runs in a square-like shape around the main section of downtown. A tram dedicated just for this loop runs clockwise on the inner track of this loop.
The Brickell and Omni loops also stop at the same stations as the downtown loop, but they run counter-clockwise on the outer track. The Brickell and Omni loops also divert away from the downtown loop to the south and to the north respectively. When the Brickell and Omni trams reach 'the end of the line', they simply reverse and start their entire loop again.
Since the Brickell and Omni loops share the same outer track of the downtown loop, be sure to look at the station's information screens to see whether the arriving tram is running the Brickell Loop or Omni Loop before boarding (they usually alternate).
The Metromover trams were pretty clean when I used them. The cars themselves are smooth riding; they don't jerk or tilt much, allowing riders to do things like work on laptops or read while on board. The cars also have cold a/c as well as Wi-Fi. Auto-announcements call out upcoming and arriving stations. There are alarm buttons as well as monitoring cameras in the cars. I always felt safe and secure as a rider, and I noticed 'rail security' riding in the cars at various times.
The stations themselves are decent. The platforms are elevated, but easily accessed by stairs, escalator or elevator. There are automated messages for station announcements and such, but occasionally you would hear a live voice over the intercoms, making you feel like the stations were well-monitored. Some of the benches for waiting were rusty and the insides of the elevators had some graffiti scribbled, but that is expected in the middle of a city. Otherwise, stations I saw were clean and operated well.
Trams arrive about every 10 minutes or so for the dedicated, downtown-only loop, and about every 10-15 minutes or so for the Brickell and Omni loops. I only used the Brickell loop and never felt like I had a long wait.
While not really an 'attraction', the Metromover is great for both transportation and for fun. It's a great way to 'get your bearings' as well as a nice (and cool) way to see all of the skyscrapers, architecture and areas of downtown Miami. Many stations are near many popular downtown sites, businesses and restaurants, making it useful for both locals and tourists alike.
Tip #1: Daytime is the best time for sightseeing on the Metromover. At night, the interior of the cars are well-lit and don't allow much of a view out because the cars' lights will reflect into the windows as you look out.
Tip #2: The Riverwalk station on the Brickell loop is high enough and in a great location to get some incredible photos of downtown and its buildings. It’s worth just to hop out at the station to take in or get a few photos of the view.
Tip #3: If you are going from one downtown loop station to another downtown loop station, it's best to use the downtown loop line. Otherwise you might end up taking the long-way-around if you use Brickell or Omni loops as they may divert away to service their separate lines before getting back to the downtown loop (and your other stop).
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.