I just wanted to post a short product review on Etymotic ER20-XS ear plugs.
https://www.amazon.ca/Etymotic-Plugs-Fi ... B00RM6Q9XW
I found these to work really well, used them once now as my 450 is a bit obnoxious. They reduce sound overall equally and don't muffle noise like a regular construction ear plug; the only muffling was on my own voice when speaking. They insert much like a regular ear plug, and I found I didn't notice them after a while. It is still easy to talk to other riders as well when trying to decide where to go, you just need to listen a bit harder. I'd recommend them for all those 4-stroke people out there (or those that get stuck behind 4-strokes).
Protect your ears people!