I've never used leg bands. Do the other chickens peck at them?
I only saw them pecking for the first few minutes, and even then it was only a couple of test pecks (nothing serious). They seemed curious rather than annoyed. After that I haven't seen anyone bothered by them.
I left them as loose as I could, but tight enough not to get caught on their feet. My girls are still young and I'm guessing only about half the size they will be full grown. So I know I'm going to be replacing them a few times. I bought the jumbo pack of zip ties.
I can also say that I LOVE having the ties on. It's so strange, but as soon as the ties went on I started noticing differences in the birds. The looked identical before, but maybe my brain is just seeing things subconsciously. But I'm finding more and more that I can look at the bird, guess the tie color, and find out I'm right. Strange - no idea why - but very cool.
It's also VERY nice to get answers to questions that help me learn more about them. I'm totally new to birds, so most of the time I'm clueless as to what they are doing. So I read as much as I can, then try to observe my own little flock. For example, I was curious if they were sleeping in the same order on the perch each night. Turns out they are!
I also like that I can track them. A few days before the zip ties, one of the girls got her head caught in the door of the run, and for one horrifying second I thought I had killed her. She was alive and seemed okay - just in shock. I wanted to keep an eye on her to make sure she recovered, but by the next day they were all acting fine and I couldn't tell which that had happened to. Good, I guess, because it meant she bounced back. But with the zip ties I will be able to actually track each bird and do a better job in the future.
Thank you to everyone for your help! I LOVE this site!