The most serious of the problems was that the drone stopped working mid-flight causing it to fall 20 feet on to concrete. We were very fortunate that no one was standing under it.
I recently just bought a DJI Phantom 2 after a bit of decision paralysis. I really like the open nature of the 3DR product line (and the fact that it has a San Diego presence is great) and seriously considered the IRIS but after doing a lot of "forum research" bad customer support when a problem was hit was a very common theme.
I don't even know how "real" of a problem this is versus just being an echo chamber thing but it was pervasive enough that I figured I'd just buy the $600 Phantom 2 as a starter and then reassess if (well, almost certainly when) I start looking for something more than just a 'starter' drone.
As an intermediate pilot myself, I'd be scared to fly anywhere near the style that the promo videos do - over open water, one mistake means your drone is taking a dive. More experienced flyers are used to the fact that flying machines crash and parts need replacing on a fairly regular basis no matter how carefully you fly. That's going to be a harder sell to people buying a complete package expecting awesome output like the promo videos.
Sometimes a propellor detaches mid-flight, or the battery unplugs due to some crazy vibration. Of course, it shouldn't happen in a good design, but users are careless and it only needs to happen once to cause a good crash.