The iO2 is the sensible choice that skips the marketing noise. It is quiet, holds a charge for ages, and cleans just as well where it matters.
What We Liked 👍
Impressive four-week battery life
Quiet and simple operation
Great value for the price
What Could Be Better 👎
Replacement brush heads are pricey
Soft bristles might feel too light
More buttons don't mean cleaner teeth
Let's be honest, you are brushing your teeth, not flying a plane. The iO5 packs in five modes and app connectivity, which is great if you are the type who needs a chart to remind you to brush the back molars. But for the rest of us, that's just more stuff that can go wrong.
The iO2 and iO3 strip things back to what actually matters. They both use the same vibrating, rotating heads that make your teeth feel like you just left the dentist. The iO2 in particular feels like a workhorse that doesn't need to show off to get the job done.
The battery struggle
If there is one thing I cannot stand, it is a tool that spends more time on the charger than in my hand. The iO2 wins here by a landslide with its four-week battery life. The others might be fancy, but they'll be tethered to your bathroom outlet much more often.
Keep it simple, keep it clean
If you want to save your pennies and get a reliable tool that lasts, buy the iO2. It does exactly what it says on the tin without the fuss.
If you are the type who needs an app to keep yourself disciplined, the iO5 is the only one that will keep you happy.