The toothbrush is very high quality and does a great job at cleaning teeth. Where it falls down, in my eyes anyway, is in the instruction pamphlet. I believe it's intended to cater for international users, regardless of language, and for all different versions of IO toothbrushes. The main pamphlet has some very confusing diagrams, as well as some fairly obvious ones; such as to look at the side of the packaging to see what modes are available in the Series 3. Unfortunately, there is nothing at all on the side of the packaging, so I looked elsewhere. A card is included specifically for the IO Series 3 which in one diagram shows three modes (correct) and below shows under a heading "Customize", four modes. If there is the ability to customize it, I haven't found it.When started up, there is no indication of which mode the toothbrush is in, you have to gauge the sound. There is nothing in the instructions to say what happens to the mode when you switch off - does it revert to mode 1, or does it start up in the mode you were using when you switched it off? There were different answers in various sites online.So, I contacted Oral B and they confirmed that the last mode used is the mode selected when starting up again.Beware if you see that the toothbrush can be reset by pressing the power button for 10 seconds - it just goes off and cannot be switched on again unless you place it back in the charger! I was informed that reset should not be used and would never be required. Also that it is not a travel lock, the series 3 does not have one. Furthermore, you may see online that it can connect to the Oral B app - it can't as it hasn't got Bluetooth, but that is most certainly not a negative for me.Having said all that, the toothbrush works extremely well. I have delicate gums so used mode 2 (gentle) and it cleaned my teeth really well, the feeling that I get after a visit to the hygienist. It is far more thorough than a manual brush, and was very kind to my gums. To be fair, I soon got to recognise which mode was which, but it would help enormously if there was some form of indication on the brush as to which mode was in use. This was explained to me that not every toothbrush in their range can have the same facilities, otherwise there would be no price range - and I get that. It needn't be fancy, just a graphic would do. But, once used to the brush, such things wouldn't be an issue.All-in-all, this is a great toothbrush and I got it at a great price from Amazon (way below the RRP), so I will forgive Oral B for the poor instructions enclosed and just enjoy having very clean teeth. Highly recommended.