Yes, people have a lot of negative reviews. But i never had a problem with it, and honestly when you are in the city it's often keep the bird of eat it. Cause it is usually hard to rehome roosters, and nobody wants to eat a pet boy! The boys are actually my favorite, they have so much personality! And once they get used to it, they stop acting weird. Haha, "Taking away the freedom to crow". Well whats worse, not crowing or not living?
Just make sure to check on the boys more frequently since they have a possibility of sometimes getting stuck on something. It's only happened to me once, but just be aware of the possibility.
I hope your little rooster does good with it! And that he can stay with you. One interesting thing i found, is it went better if i put the collar on before they started to crow. After a bit, i experimented by taking it off, and i don't think the rooster knew he could crow. He wandered around making clucks and chirps, but didn't crow. After about a month i think he crowed once, but it was very quiet, and he only did it every now and again, not all the time.