I love my MB! I bought it on the recommendation of my sister and LOTS of internet research. I have been using it for 6 months and have not had a prob fitting anywhere- mind you I go thru the wheelchair aisle in supermarkets by habit now but I haven't ever been stuck anywhere. It folds out and collapses so easily. Everything about it is easy actually....and so smooth. I can also guide it with one finger- truly!
I think they (MB) are looking into a toddler attachement but if/when another bub comes along I also use a sling (Ergo) alot and so can use both together...