Philips Sonicare ProtectiveClean 4100

Brand: Philips Sonicare 9900 Prestige

The cheapest Sonicare that still keeps the two features dentists actually ask for: a pressure sensor that hums a warning when the brush is pushed into the gum, and BrushSync, which lights a reminder once the head has done its three months. One cleaning mode, clean, with two intensity settings on the HX6810 and HX6817 versions. Battery life runs to about two weeks per charge, and the brush sells in the 45 to 60 dollar range depending on colour and bundle.

Suited to anyone moving from a manual brush who brushes hard by habit, and to households that want the sonic feel without paying for an app. Skip it if a travel case matters, since most retail bundles ship with only the charger, and note that the head replacement light cannot be turned off once it starts glowing.