On our last trip to Orlando (March), the security line was absurdly slow - until suddenly it wasn't. We stood in the line for an hour or so, and had barely made it past the point where they check boarding passes, and then all of a sudden the line started to move quickly. We were only another 10-15 minutes from that point. It was as though they gave up; when we got to the scanners they were telling people to leave shoes and sweaters on, and have everything else (cellphones, laptops, etc) packed in bags, which appeared to be subject only to a cursory scan. This was the regular line, not the TSA pre-check line. We took the Magical Express, scheduled 4 hours before departure time, and only had enough time at the gate to grab a quick bite to eat before boarding.
I'm not usually one to leave much extra time at the airport. On the trip down, we very nearly missed our flight out of Montreal (as in, the gates were closed and they were rebooking us when the pilot took pity and let us on), because we planned to arrive at the airport 1.5h prior to flight time, got there a bit later than that for reasons out of our control, and the lines at both security and customs were very, very long. Flying from Ottawa we usually aim to be in the parking lot somewhere between 75 and 90 minutes prior to departure. But even I would not leave less than two full hours at MCO unless they get the TSA situation under control. That's minimum. Three would not be overcautious. YMMV.
