Hi!
We are using IAD in Estonia for 10 years now.
The most common malfunctions are linetwists from a bad body position in exit.
The most scariest malf. was for me when my student crabbed the pilotchute bridle and it wrapped around her hand, but she managed to solve it. She had like 7 seconds of freefall but she was okey.
I attached some iad exit pics.
The pictures are made in an annual camp in a small estonian island.