These are almost certainly the best I've found so far. I've tried 3 different models so far, but these ones provided the best attenuation characteristics.
Use
I use these together with headset type ear protection while playing the ocarina, as it can get pretty loud at the high notes and cause ringing. But with these 2 things together, ringing is now a thing of the past. :)
pros & cons
So the pros are, quite good attenuation, and options for the degree of attenuation you require
On the negative side, I'm not sure how much I'm supposed to insert into the ear, i try not to insert too much, as a) those are my ears, and b) it gets attached to this thread, and it seems a bit delicate, so I didn't wanna risk pushing it so far in, that pulling it back becomes a headache, in case the thread fails...
Summary
I would definitely recommend getting this, assuming you would like to protect your hearing, while playing music... Maybe also look into getting some over the ear ones to use as supplementary protection