I use a line and a retractable thing depending on where I am and what I'm doing. Poppy still chases the hens so the retractable is handy for taking her outside for quick wees etc. On the beach or park & woods I like a line.
People don't use retractables the way they are intended so often and it drives me mad when their out of control pooch wraps the line round your legs. Why don't they just push the button to stop the dog?

It's actually really easy, like TW said I hold it like a horse's lunge. It's looped in my left hand and I hold it like a horse's rein in my right. I give Ella as much lead as she wants and I think is appropriate in that situation. If we do encounter another dog and I think it's ok for her to go greet that dog, I walk with her and the lead is normally about the same length as a standard lead. So it's slack but not dragging on the floor. I observe her closely and if she was to show signs of aggression or lunge, I can hold her back easily, but I can also give her space to retreat and move away if she wants to and there's no pull on the lead so there's no chance of her feeling tense because of that.
With a retractable lead I couldn't do all this. The lead would constantly be tense and also it's much much harder to reel a dog in on a flexi lead. You have to move your hand forward, click the button, pull your dog back, open the lead again and move forward etc. and in that second the lead is open again, the dog could lunge forward without you having any control over it.
Unless you grab the lead with your other hand and that has proven really dangerous and normally it even says on the lead packaging not to do that (they do come with a safety warning...).
I'm not saying that accidents don't happen with long leads. At my first attempt of tracking with Ella, she bolted and I was holding the lead the wrong way (instead of coming through my ring finger, I held it between my thumb and index) and I had a nasty burn.. But that was my own fault to be honest

I never use them either, much rather use a long line if I need distance control.

In just my own sphere of friends I have seen burns on fingers and calves, a dog nearly garroted by running into someone elses lead, snapped ones, ones where the locking mech has broken and my favorite - the one where the dog gets to the end of the line and either the dog does a back flip or the owner lets go and then we have a terrified dog running hell for leather being chased by a big plastic handle that keep smacking on the backside!

As to the question - Do I think they are safe? That would be a resounding NO

I feel it's important to use what you feel comfortable with. Accidents will happen no matter what is used - lines breaking (even short leads), burns (even short leads).

I feel comfortable with the flexi and, more importantly, know how to use it to best effect with my dog. I feel less comfortable with long lines (which I have used with client's dogs when the need arose).

I add the extra precaution with the flexi of tying (and sewing) a loop (actually the handle part of a short lead) to the plastic hand grip which goes over my wrist so that, if the worst should happen and I lose grip on the handle, the lead is still in play

I just think they should be avoided for the most part. I'd never recommend anybody use one... especially not owners of large dogs or dogs that may bite or get nasty if they break loose. They simply aren't reliable enough in those situations.

Well I use one, like to thing properley, if I'm going into town I use a normal lead but any other walk I use a flexi lead. I think it's great as when Rosie can't be let off she has the freedom still to have a sniff and wander. I wouldn't be without it, tbh

hate them, my cocker spaniel ran to the end and it just came out and she kept running
ATD x

Been using them for over 30 years now with all sizes, breeds and ages of dogs, our own and fosters. Never had a problem but them I walk alone, always lived in quiet areas and teach each dog how to walk on one sensibly. I wouldn't be without them and am still using the first ones we bought 30 years ago for our GSD's.

This happened to me, as well. One snapped in half, also. I don't trust them, the chance of them breaking of malfunctioning is to high for me.

Very remiss of me, I ask a question and then never come back for the answer

Florence thank you for your explanation.
I don't think I have the experiance or co-ordination to cope with a long line. I would probably lassoo more people than I would round up with a retractable.