We wear parachutes in the ASK-21 which gives me mixed feelings because we operate at such low heights most of the time. I don't know if I'll have enough altitude to bail out when the ship is falling apart under my ass. I'd prefer an ejection seat.
What altitude can you jump out sucessfully?
For hang gliders:
Officially: 50 meters
Practically (often enough prooven in RL): 30 meters
IIRC that height is defined as "without major injury".
There is a very interesting study by the German hang gliding assoc (DHV), where they plotted the seriousness of the result of accidents versus the seriousness of the cause.
The interesting thing is that it does NOT go up all the time but actually goes down for some part. IOW with a more serious accident you are safer. The reason is that with a really serious accident, say collision with disintegration of your craft, you will throw the parachute without a further seconds thought! With a middle serious accident, people often try to ride it out and then crash down from medium height preoccupied with controlling the craft instead of concentrating on throwing the chute.