We just used Tiffany Town Car for our trip last week and it was great...smooth with no problems. We had a 6:30pm departing flight and we were told by TTC that we'd be picked up at 4:30pm...the driver actually arrived early around 4:10 so we grabbed our luggage, a drink from the store and left a bit early. We had plenty of time to get through security, grab a snack near our gate and be on the plane. We didn't ask to be picked up at 4:30, they told us what time to expect them. I guess if we would have liked an earlier time we could have requested it; I just didn't bother as I figure they know the traffic patterns in Orlando better than I do since driving people around is their job.