Both my leads are natural horsemanship leads, they are 10ft but have no snap. Both came with bull snaps which I absolutely HATE. I also dislike twist snaps and bolt snaps aren't much better.
The reason I like my NH leads is that they have the leather poppers built in so they have bite if I need to be firm. I have written my name and my horses' names on both of them.
I free lunge in a round pen rather than using any lead or line. I just find it easier to manage. My horse can't get tangled and I can't get the rope around my feet.
If I led with a 'normal' lead I would have to have a schooling whip on me the whole time I handle as my young horse can get rude and I need something that has some bite to put her in her place when she steps out of line. My older horse is always respectful in a rope halter but gets rude in a flat nylon or leather halter, and I like having that little extra just in case.
I do not, however, subscribe to NH teachings. I do not like Parelli, I don't want to handle my horse in that manner. I have used some of the PNH games and methods and have had success... I am just not into the religious "this is the only way" bull that PP and his followers spout.
I will not use a lead that is likely to give me rope burns IF my horse spits the dummy. Rope burns are painful and all horses have their moments.
Once all that has been addressed and my ropes have a) no snap, b) poppers on the end, and c) less chance of causing rope burns, I then look at colour... has to look nice on my horse after all!