Other then the obvious, saving my hearing, earplugs really do take out that feeling of speed. I was shocked at how much more confidence I had riding yesterday with them. Went up to Squamish after work for a ride. Went few times up to Porteau Cove, but never further, mainly due to time/weather restrictions. When i rode without earplugs, I always had that sense that I am going too fast and would slow down in a lot of turns thinking I was going way too fast (looking at speedo I was going below limit lol) On yesterdays ride wearing earplugs, I was able to keep my speed up and concentrate on turns and lines to take, not worrying that I am going too fast. Sometimes I was going 10 over limit in the turn and never noticed it simply because it didnt sound like I was going fast.
I was using silicone ones that mold to my ear. I tried foamy ones that you roll and insert into ear canal, but they do not work well for me. They kept falling out and hurting my ear after a bit. Silicone ones are much better for me. No problems with them riding several hours (yesterday to Squamish and over the weekend to Mission and back)