No experience with them, but Ford used to be the "Wagonmaster", making more station wagons than anyone else. The FLEX looks to me to be a modern version of the station wagon. I'm not knocking station wagons. I had an 85 Crown Vic wagon. Excellent car. Anyway, you might find some useful info at the link.
We have a 2012 model with the Eco boost engine. Great car for trips and hauling a lot of people (up to six with three rows of 2) or stuff. The road manners are quiet and stable, the ecoboost engine does make for speed and quickness if you want to go there. Get roughly 19 mpg around town and mid 20's on highway. Very comfortable interior with a like it or hate it exterior.
When GM told us in 1995 that they were going to cease station wagon production in 1996, we protested but were told that station wagon buyers would simply switch to SUVs or minivans. I spent the next five years buying GM station wagons in nice condition for our used vehicle inventory and paying out-of-the-book money for them, as they were a hot commodity. Our customers told us that if they wanted to drive a truck or use a stepladder to wash their car, they would already have an SUV or minivan. Every time our district sales manager stopped in, I would make him stand out front for a few minutes and watch the Subaru Outbacks and Ford Taurus station wagons drive by. Then I would show him what I was paying for those used GM station wagons. But by then, it was too late.
In its infinite wisdom, GM did realize its mistake and suddenly we had "crossovers" and smaller SUVs. How smart of them!
I have a 2011. Had it for 2 years now. Love it. Non eco boost engine but it is AWD and it gets 25 highway, I drive the speed limit. City driving 21. It is great in snow with AWD. never spin a tire. Has all kinds of power. I would love to have the eco boost engine. We have bench seat in the middle not the most comfortable for 3 but it works when we have used it. Great interior room. Lot of space behind second row seats. My friend has a 2009 and they are the reason we bought ours.
I have a 2010 Flex Limited with EcoBoost. Not a race car but has the feel of a small V8. Six speed transmission helps the MPG. Mine gets 24 MPG on the road and 18 MPG in the city. At 70 MPH it runs just under 2000 RPM.
It's a lot of car. When I go to a big shoot I carry my mini golf cart in it and all my shells, guns and luggage. I like mine and intend to run the wheels off it.
Had one (2010) but found it didn’t quite work real well for our shooting equipment. The rear section is slanted towards the tail gate so without modification our gun cases kept sliding and bumping the rear hatch. Made some nasty marks and you were never quite sure if they would fall out when the hatch was opened. Also hit our heads a lot, especially when we parked up hill, just not enough clearance. Modifications made to take out the slant and add shelves, but still hit our heads.
Other than that, loved it! Plenty of room, can get 6 adults in without hunching over. Was loaded, essentially a Limited without the price tag. Have since traded for a Ford MXT. Not quite as much slant, much better head clearance and a bunch of safety features the 2010 Flex didn’t have.