Instruct: Classify Amazon reviews into positive or negative sentiment
Query: They work like they should

These fit on my Oral-B Professional Healthy Clean Precision 1000 Rechargeable Electric Toothbrush and buying them on Amazon saves you a few bucks than in-stores. As for the electric toothbrush's effectiveness, well, I left a review on how useless it was. I'm still using the electric brush but it's as effective as any manual brush I've had.