Let me get the obvious out of the way first, this is a sponge, and like your dish sponges and other cleaning sponges, it will fall apart/degrade over time. It's just unavoidable. That being said, these are excellent bottle brushes. My son drinks about 6-8 bottles a day and for some unknown reason, we wash all of them by hand instead of using the dishwasher and then sterilise them. Each brush on average will last about 3-4 weeks and I now use them to clean our glasses and mugs as well. We wash our son's bottles first in fresh water all the time and then do the rest of the dishes afterwards so the brush never comes into contact with food particles. The nipple brush is excellent for getting into our Dr. Brown bottle nipples and cleaning them out which is an added bonus.
I have 2 complaints about this product but not significant enough for me to deduct a star.
1. As the bottom unscrews to access the nipple brush, the cavity where the nipple brush sits will get soap in it so you have to remember to rinse it out after use to avoid soap scum. 2. The base while meant to be a stand does work, its not very wide so simply bumping the sink and a heavy thump on the counter knocks it over on occasion.