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AquaSonic Black Series Ultra Whitening Toothbrush vs Oral-B iO Series 9 Rechargeable Electric Toothbrush

Which one has the downsides you can live with?

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The short answer

AquaSonic Black Series Ultra Whitening Toothbrush ranks higher (#2 vs #4 of 8) and scores better on battery, replacement head cost. Oral-B iO Series 9 Rechargeable Electric Toothbrush wins on cleaning feel, gentleness, durability.

The biggest complaint about the AquaSonic Black Series Ultra Whitening Toothbrush is intense vibration, not very gentle; for the Oral-B iO Series 9 Rechargeable Electric Toothbrush it's very expensive. Pick the one whose catch bothers you less.

Side by side

AquaSonic Black Series Ultra Whitening ToothbrushOral-B iO Series 9 Rechargeable Electric Toothbrush
Rank in electric toothbrushes#2#4
Price tier$$$$
TypeSonicOscillating
Amazon 1–2★ share6%6%
Overall score3.73.8
Cleaning feel4.04.5
Gentleness2.04.5
Battery5.03.0
Replacement head cost4.52.5
Ease of use4.04.0
Durability2.54.0

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

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.

  • 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.

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.

  • 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.

Who should pick which

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

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

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