I have no problems so far with mites on my brugs. And believe me, we have a lot of everything here in FL. When I used the Bayer 3-in-1 on them, it only lasted a few months then the mites and other bugs developed immunity to whatever the insecticide in it is. That's the fatal flaw with systemic insecticides.
Soapy water also works but is not easy to cover with, and I also found it makes the plants photo-sensitive i.e. the leaves burn in the sun if the soapy water is on them when the sun hits. I had to spray with the soapy water in the evenings, then rinse the plant off with the hose the next morning, early.
Now, I just make a point at least once a week to spray/drench the whole plant with the hose, being sure to wet everywhere, including the undersides of the leaves. Mites hate wet weather, and they seem to be washed away by this treatment, so I'm just going with what's working now. Yup, plain water sprayed from the hose. Once or twice a week minimum unless it rains.
