It is recommended to use a different tooth attachment every 3 months due to hygiene and bacteria. So this is what I do too. I can't tell the difference between the attachments. However, I do know that this variant works well.
Only these brushes are very expensive, even though you get them with 1+1 for free. Unfortunately, that is less. But good for good teeth, you have to pay for it. I'm looking for another electric toothbrush though, so suggestions are welcome 🥰