If you get a bin of zip ties for like 6 dollars at Menard's or places like that, it has a selection of colors - red, yellow, green, black and white, in the size that is good for leg bands. I use them and they work fine. Just make sure they are on loose enough, and use a fingernail clipper to get the dangle part off, right down to the nub, but not so close it would pop off too easily.
I don't know how many chickens you have, and how many you want to band. I use green for my potentially naughty chickens (the ones I am watching to see if they keep pecking) and I don't tag all of mine, just the ones that need to be IDed for some special reason like "don't cull, or this one is laying". The bin doesn't come with a ton of each color, which is the problem, but it comes with quite a few.
I would worry about beads being pecked at (mine love parrot toys with beads) and the chickens tripping or getting caught on something. You never know what those buggers will get into.
overall, though zip ties do work fine. Just make sure you leave like a few centimeters of slack, so that it still spins easily around the leg, so that you can trim them off later if need be. And if you are putting them on chicks, make sure you leave enough slack so they they have room for their legs to grow. check regularly to make sure they are staying loose.