I just bought and used for 3 weeks in Bahamas spearfishing. For the most part it is manageable BUT only if you avoid the standard invert and descend dive approach and sort of weasel under at 45 degree angle instead. If you do a typical invert and descend dive I find the thing shocks my lower leg. I tried to watch what was happening and looked like it was flopping back on me. I used rubber band around mid fin to hold in place but was worse that way than free hang. Any suggestions? Also an interesting question from my wife. What information / assurance can you provide that there is no risk to stopping your heart if this thing hits your chest?