"I bought this for my Lab when she had a cut that she wouldn't stop licking. It works great and was never damaged from her banging into things. A couple places on the edge got a little dented, but that didn't make a difference. It's a lot more flexible than other plastic e-collars I've used, so my dog could sleep and lay down in it comfortably.
The only thing is that I think it could have a bit more padding - it only has a thin strip that I don't think really does anything for comfort. Also, one time it did come unsnapped when my dog hit a table running, but it only happened once."