The search continues as a problem occurred to me: both the Baby Jogger City Mini Double and the Valco Ion 4 Two have to have car seat adapters which compromise the flat fold of the stroller. In fact, you’re not even supposed to leave the adapter on the Valco Ion 4 Two when folding. This video The BJ City Mini Double car seat adapter sticks way out if you leave it on after folding the stroller. This video shows the problem in detail—
These car seat adapters aren’t easy to install and they take a significant amount of time. Sadly, I am going to have to say this is a deal breaker for me. I know my future double stroller will spend a lot of time in the back of my car, folded up. I cant have a big metal thing sticking up taking up space.
On the upside, the Peg Perego Aria and Zooper Tango are looking promising.