We've used Lyft/Uber from MCO a few times, follow the directions in the Lyft/Uber app and they will get you right to the spot to get picked up. We've never had a bad experience with it at Disney World or Disneyland.
The lesson I learned was in Chicago you're better using the taxi system since most the Uber/Lyft drivers don't live in Chicago so they don't know the short cuts, plus had 2 drivers bail on picking us up due to some of the 1-way streets - at least that's what the staff at the Sheraton told us.