This item enables the assist to be turned off as well as setting the other modes, which cannot be done using the standard controller without holding down the button.
I decided to put the buttons and cables under the handlebar tape and the rubber brake covers, which can be done with care. It would be nice if the item was supplied with spare sealing tape and a 15mm cutter especially as it is expensive for what it is.
Hope this helps, that said I would recommend adding this item to your bike.