Well we are only two... and Mears shuttle service (for 2) is almost half the price of a shuttle. I'm not trying to be a real miser here, but I don't think I'll be bothered by sharing a van with others after sharing a plane...
We are not staying at Disney for the first half of our trip, but we will be moving to a disney resort later and use the DME for our return trip to the airport.
But really, what horror stories... I'd really like to know.