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Oral-B iO Series 9 Rechargeable Electric Toothbrush vs AquaSonic Black Series Ultra Whitening Toothbrush
Which one has the downsides you can live with?
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The short answer
Oral-B iO Series 9 Rechargeable Electric Toothbrush ranks higher (#2 vs #4 of 10) and scores better on cleaning feel, gentleness, durability. AquaSonic Black Series Ultra Whitening Toothbrush wins on battery, replacement head cost.
The biggest complaint about the Oral-B iO Series 9 Rechargeable Electric Toothbrush is very expensive; for the AquaSonic Black Series Ultra Whitening Toothbrush it's intense vibration, not very gentle. Pick the one whose catch bothers you less.
Good for: People who want app coaching and data
Its catch: very expensive
Check price on AmazonGood for: Tight budgets (8 heads in the box)
Its catch: intense vibration, not very gentle
Check price on AmazonPaid links. We don't list prices — they change daily. Neither one feels right?
Side by side
| Oral-B iO Series 9 Rechargeable Electric Toothbrush | AquaSonic Black Series Ultra Whitening Toothbrush | |
|---|---|---|
| Rank in electric toothbrushes | #2 | #4 |
| Price tier | $$$ | $ |
| Type | Oscillating | Sonic |
| Amazon 1–2★ share | 6% | 6% |
| Overall score | 3.8 | 3.7 |
| Cleaning feel | 4.5 | 4.0 |
| Gentleness | 4.5 | 2.0 |
| Battery | 3.0 | 5.0 |
| Replacement head cost | 2.5 | 4.5 |
| Ease of use | 4.0 | 4.0 |
| Durability | 4.0 | 2.5 |
Price tiers: $ under $50 · $$ $50–120 · $$$ over $120. Highlighted = clearly better (a score gap of 0.3 or more, or a 1–2★ share at least 3 points lower). Scores are explained, with sources, on each product's page.
Top complaints
Oral-B iO Series 9 Rechargeable Electric Toothbrush
- Very expensive
CNN Underscored calls the roughly $330 list price a tough sell even on discount. Electric Teeth puts the US suggested price at $299.99. Amazon's summary says value for money is mixed, with some owners finding it overpriced.
- iO-only heads and a mold-prone gap
Electric Teeth puts iO heads at about $8, roughly twice the price of standard Oral-B heads, and says mold can build up in the gap around the magnetic head mount. Wirecutter notes some customer reviewers clean that junction daily.
Source: Electric Teeth, Wirecutter - Tracking accuracy disputed
Electric Teeth found position tracking inconsistent, sometimes logging the wrong zone, and worse for left-handed users. CNN Underscored, by contrast, found the app accurate every time it tested it. Amazon's summary calls tracking mixed.
- About 12 days per charge
Electric Teeth usually got about 12 days against a 14-day claim, though the charger refills it in about 3 hours. Amazon's summary says some owners report it doesn't hold a charge.
AquaSonic Black Series Ultra Whitening Toothbrush
- Intense vibration, not very gentle
Electric Teeth found it less gentle than Sonicare or Oral-B, said even the soft mode didn't feel very soft, and described the bristles as stiff. Amazon's summary calls the vibration level mixed and pretty intense. Some 1-star Walmart reviews say the vibration was hard to tolerate.
- No pressure sensor
CNN Underscored says the missing pressure sensor is the main reason it didn't earn a top spot. Electric Teeth also lists it as a con.
Source: CNN Underscored, Electric Teeth - Cheaper build; some die around 6 months
Electric Teeth says it feels cheaper than premium rivals (the chrome rings are plastic) and notes some reports of breakage; the warranty is 1 year. Amazon's summary says durability is mixed, with some owners saying it stopped working after 6 months. Walmart low-star reviews mention dead chargers and heads that don't stay on.
- Small heads
CNN Underscored notes the included heads are on the smaller side, and a Walmart 1-star reviewer compared the head to a toddler's.
Who should pick which
Pick the Oral-B iO Series 9 Rechargeable Electric Toothbrush if
People who want app coaching and data
Building better brushing habits
Oral-B users who want the quieter iO motor
Skip it if: You won't use the app; You're on a budget; You're left-handed and want reliable position tracking
Pick the AquaSonic Black Series Ultra Whitening Toothbrush if
Tight budgets (8 heads in the box)
Travel (case plus a long battery)
People who like a strong buzz
Skip it if: You have sensitive gums or teeth; You tend to brush too hard and want a pressure sensor; You want premium build quality
We don't list prices — they change daily. Paid links.
Neither one feels right?
If both catches are deal-breakers, start here.
Wirecutter's long-running top pick, with cheap, widely available heads. It is louder than sonic brushes, and its pressure alert is easy to miss. Owners also report units that stop holding a charge.
Its catch: stops holding a charge or dies earlyA third option · #6Oral-B iO Series 3 Rechargeable Electric ToothbrushThe cheapest way into Oral-B's quieter, gentler iO motor, with a visible pressure light. It locks you into pricier iO-only heads, and it has the highest share of 1-star Amazon ratings among the big-brand picks here.
Its catch: stops working after about 6 monthsAll 10 comparedSee every electric toothbrush, rankedEach one's biggest complaint at a glance, with the full ranking.
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