Brushmo Sonicare Replacement Toothbrush Heads 8PK

I bought these brush heads before and the old batch is running out, so I bought a new pack of 8. 1. Good quality. The bristles have the right stiffness, similar to the original Philips ones, maybe slightly softer. Fit on the brush handle very well. 2. Vibration is similar to the original ones. 3. A lot cheaper than the original ones. 4. The Philips brush heads have some sort of built-in sensor (the small dark square shaped thing?) in the end where to plug in the handle. When pressed harder against teeth, the original brush makes a different sound which is probably designed to alert users not to use too much pressure to avoid damaging teeth and gum. These alternatives have no such elements for feedbacks. Maybe that's why they can be made at much lower cost. But since the vibration is already strong enough, I normally won't press too hard on my teeth. So, the lack of alert is not essential for me. 5. Last for a long time. Each brush head can last for a few months. Occasionally I use vinegar to sock the head to get rid of the calcium residues from water, and I have a small sonication cleaner to double clean the brush heads. With proper maintenance, they can last much longer without much problem of bacteria contamination.