Overall, my skin is looking good, but I have developed a few weird pimples, in a line across my upper lip. Not so attractive. I assume I was putting too much pressure on the brush.
When I got my Mia 2, it came with a Sensitive brush head attached. I got a coupon in the box for $25 off on a purchase, so I ended up buying four replacement brush heads of 3 different types. I decided yesterday to try the Acne Cleansing brush head I had purchased and it seemed a lot gentler.
I fussed and fretted for a while about whether it was worth exchanging the other brush heads for the acne version. Each brush head is around $25, or $20 if you buy it in a twin pack, so I decided to call customer service and just see how much they'd charge to ship the brush heads back and swap them out for the acne kind. They are sending me the new brush heads and a mailing label to return the ones I don't want, no charge, so I am very glad I called. It was worth spending 10 or so minutes on hold for that good news.
If you have acne or sensitive skin and are considering a Clarisonic, consider just starting with the Acne Clarifying version of the Mia 2, which will save you the cost of swapping out a brush head you might not want to use. It also comes with an acne-specific cleanser. I didn't see this as an option when I shopped, or I probably would have gotten it.
Despite this little hiccup, I am still happy with my Mia 2. I am now using it with Philosophy Purity Made Simple Cleansing Gel, which seems appropriately gentle for use with this tool.