1) Quality Shimano equipment needs to be tuned in by a good bike shop.
2) One design flaw: headtube nuts work loose constantly - I installed a screw to keep the nuts tight - works well.
3) With axle positioned for everyday use, the DragonFly has limited traction (e.g., won't ascend an ADA ramp). Because I live among hills I had a second axle mounted on amputee adapters to which I move my rear wheels when using the Dragonfly, and now it works beautifully even up long hills steeper than ADA.
4) Initial setup is a royal pain. Because it's designed to fit so many configurations, getting it right for one is tedious, iterative, and time consuming. After the setup is tuned in though, it's real sweet. Stay close to tools and help until it's thoroughly tuned in. It took me weeks to tune it in.
5) Use thread locker on the small fasteners near the headtube.
6) Coaster brake works very well, especially when good traction exists.
7) The standard hand grips are marginal; I'm hoping to upgrade to Bike-on's ergo grips.
8) Inner tube came installed so its angled fill valve was not accessible.