Great exchange for plastic I've been using [SEP] Handle is comfortable, bristles are perfectly firm - not too soft/too hard.  After a week of use, not a complaint.  I have used the Bite brushes and find these much better in terms of comfort. Will definitely purchase again.  Edit: Have been using these for over a month now and they are still 5 stars.  All bristles remain intact and are lasting longer than the old plastic ones I've been using my entire life. Strong recommendation for these toothbrushes.