My plan has been to chip the girls because I hate breakaway collars. I don't trust them to break, but something said in another thread has been bothering me. The poster said a collar means "I have a home.". I feel the same way so after mulling it over I went to PetSmart to look at my options. They have collars that have a traditional buckle with an elastic segment to help the collar come off if the cat gets stuck. Do any of you use these? How effective are they?