You have to follow the directions, once I did one can the rest where easy and took only a few minutes each to install.
I use them with the FEIT DIMMER which Costco had two packs for $15.00.
Not sure they work with other dimmers well.
No buzzing or flickering yet and a fellow shopper was picking up more as he has been buying them over the last two years adding them with an addition to his house with no problems or failures.
I STRONGLY SUGGEST you open the packages to inspect them as I had read there was a number of reviews saying that there was finish inconsistency and scratchs on the outer rings which I also found on some when I looked before to pick out thr best before buying them.
I bought mine at the Dedham, Massachusetts location they had them at the Waltham, MA location also.