My favorite pair of earbuds are these, the foam blocks out a lot of noise, just roll it in your fingers before inserting it.
I have about 1600km of use with the SENA headset. Yes, they are used with a communicator, but I don't think there's any difference between these and music-only in-helmet speakers. It is VERY handy to have an all-in-one unit attached right to the helmet. No more fiddling with earbuds or wires...very handy. Sound quality is ok, you will miss bass though (common issue with every in-helmet speaker I've ever read). They were plenty loud enough, even with earplugs in, but I think the SENA has a built-in amp.
EDIT: I've used a similar bluetooth unit that JIMTOE refers too. Agreed, very handy to pause, REW, FF music. BUT...it's one more thing to charge, store, fuss with, keep waterproof, etc.