We used it both ways last year and I agree it was economical, super safe, clean, and very easy. We are a family of five and we each had our own suitcase (the size above the carry on size) and the youngest, DS who was 9, had no problems getting his suitcase on and off like the rest of us.
The return to the airport was on a Monday morning. We got off the ship around 10-10:30ish and walked to the nearest stop. It wasn't busy at all. The worst part was the long customs lines at the airport, but that had nothing to do with the Skytrain!
I would totally use it again and recommend it!