Take the Maclaren! They are THE perfect WDW stroller, as everyone who has taken one there knows!
I'm paranoid about mine, because it took me so long to discover them, and it is -so- integral to our getting through a trip without meltdowns (on anyone's part ! Those of you who have tried to cart a bulky stroller on buses and up stairs know what I'm talking about.) BTW, for those who have recommended that she take an umbrella stroller instead; a Maclaren -is- an umbrella stroller, the best-made umbrella stroller in the world.
They are aluminum, and actually weigh less than a cheapie Walmart umbrella stroller that's made of steel, even though they have full hoods, legrests, baskets and variable recline.
I agree that most strollers are taken by mistake, but I'm not sure that Maclarens are common victims of that; they are still rare in the US, so you don't see legions of them at WDW. What worries me more is the eBay risk. Disney is aware that some people steal strollers on purpose, but when I've asked, I've been told that they usually turn up in a few days, having been abandoned somewhere on the property when the thief no longer needs it. CM's I talked to said that Maclarens are not commonly seen in the Lost Property room, however.
With that info in mind, I decided that the best compromise for me between peace of mind and aggravation was to lock the frame of the stroller so that it can't be folded. I lock it once when I arrive at a park, and don't have to mess with it again until we are ready to leave. I use a regular combination padlock that has a long 4" hasp, and I lock it across the hatchwork at the back of the basket, where the lift-latch is. I also put a large laminated label on it that identifies our resort and dates of stay, so that it can be returned to me immediately if it does manage to wander. Our name and home address are on return address labels shellacked onto the underside of the frame in 3 places. These precautions enable me to stop worrying about losing it, so that I can relax and have fun.
When we travel by air I slip a ripstop fabric sleeve over the main body of the folded stroller, with the wheels and handles sticking out. This protects it from dirt, rain, and accidental unfolding while it's being moved. I've gate-checked it more than 30 times now; no damage so far.