This will depend on what you’re looking for in a brush and what type of bottles you’re using. There’s really not anyone feature that you have to have, except a nipple brush, which almost all brushes come with these days. You’ll want to look at how the brushes are stored, whether they’re dishwasher safe, and the type of material. Some come with storage or drying racks. Compare a few and decide which features will work best for your household.