I have always selected helmets based on them blocking windnoise, so that meant only full face, and tight.
I wear earbuds with them sometimes.
I have only started using earplugs, though others I know wear them all the time (they don't have tight fitting helmets like mine though). I got the eargasm ones, and they do work surprisingly well. I can just hardly hear the engine, but can hear the sena (bluetooth) without any issues.
I also got some decibels, but with the eargasm ones working good at their rated 15-21 nnr, I opted not to use the decibels (31nnr) except for sleeping.