I have one similar to the green one in the first picture, but the ends are more sharp. I consider this my scalp scrubber. The silicon is more dense and downy doesn't really flex.
I have another one that looks like the first picture. The teeth are rounded with some flex. It is battery operated and it vibrates. You can use it in the shower but I use it dry. This is my massager.
So while they look almost the same, they feel different. I don't use my scrubber often. It doesn't tangle my 4c hair, but I suspect that I end up with breakage when I use it. Coincidentally, I also seem to use only use it at the time of year when I she'd the most so I can't say this for certain. I've used it on my children (looser hair texture) without issue, so it could be in my head.
My massager on the other hand, I use more often and without issue.