So far we have always used the older and slightly softer version of heads with yellow inlay. These are now equipped additionally with bristles of varying heights and appear considerably harder than the other heads to me. In my opinion, about too hard because I have to reduce the performance of the toothbrush by one notch to me not to harm my gums. If it is only habit, okay, it remains permanently here are the heads for me not applicable. So far I would say the cleaning power with these heads should be higher, as long as the gums it can withstand ... but so far I found the older version enjoyable.
