If you can afford it, I would have to vote for the Poly. With 4 young kids and a double stroller.... that monorail would be REALLY great for you! I like to be frugal myself - however, I definitely enjoy splurging on vacation (so long as its in the budget!). I didn't stay at the Poly (but I did stay on the monorail) and I have to say, when the kids fell asleep in the stroller it was really nice to just roll onto the monorail and let them keep sleeping!