Tony they can be quite safe mate, they come out of the weed easier than a pendulem lead, just be mindfull the lead comes off the swivel.
I personally wouldn't use in dense weed though. just incase you crack off.
what type of rig would you use when fishing in dense weed then. I have had so many suggestions but everyone seems to think differently lol. at the moment i am thinking of using an in line running rig.