Hmm... my impression of how safe it is to perform ring flight effects with a reel is steadily plummeting. There doesn't seem to be a single one that people have not encountered scary problems with.
One thing I noticed with the IMAKulate ring flight (which broke) - it uses a very powerful and fairly quiet reel, but seemingly no reel is designed to endure the constant *SMASH* as the ring clip thunks into whatever stopper mechanism is used. Or rather, it's not the reel's fault - most usually it is the thread/wire that isn't up to the job, or the knot used comes undone, or even the clasp or clip is made of too brittle a metal to withstand regular blows like that.
I used to do a fair bit of climbing, and one thing is drummed into you - ropes are fine and last for quite a while if you put gradual pressure on them i.e. abseiling down stuff or suspending you, but if you take a significant fall and are saved by the rope, replace the rope. There are very, very few materials that can withstand sudden, sharp, high velocity jolts on anything like a regular basis.
I expect all of us who have given reels a go have sworn once or twice when it painfully whips your finger because you were holding it too close to the entrance of the reel...! Think how painful that was, then think that the thread, the knot, the metal of the clip - they are supposed to withstand the full brunt of that power every time. I have never come across a reel/thread/clip arrangement that could withstand even 10 full length, full speed retractions without something giving
Certainly if
any of the components are plastic you don't stand a chance.
More and more, I am inclined towards reel-less ring flights...