I use a competing item from http://wind-blox.com, which I have posted about in the past. I switched helmets recently to be able to install my ginormous rear view mirror (the previous helmet didn't have the slots I needed), and I quickly realized I needed to move my wind-blox over! Dollar-for-dollar, one of the best purchases I have made as far as increasing enjoyment of cycling. -- Fitz Chivalry
When you cycle, of course, with a bicycle helmet on (!) Therefore, it is smart that you can add WindBlox to the helmet straps, in front of the ears. The barrier ensures that the wind is prevented from whistling directly into your ear canals. Thus, wind noise is significantly reduced.     -- Aspie DK blog
We’ve covered Wind-Blox before, and been surprised by the results. If you’re sick of getting freaked out by people whiffling past you without warning, Wind-Blox can help.  These seemingly simple strap covers velcro in place in front of your ears to reduce wind noise at speed. This, in turn, lets you hear much, much more of what’s going on around you and behind you. The refined Wind-Blox Pro edition is a slimmer design than previous iterations, and doesn’t interrupt the clean lines of your helmet strap as much. In testing, they work a little better than the original Wind-Blox to, especially when you’re moving pretty fast down the road. -- Bek SLOCyclist.com
If you cycle, especially if you cycle around traffic where hearing is crucial to your safety, I would consider spending a few bucks on Wind Blox to improve rides. -- Sarah McMullin SimplyFitandClean.com
I used the Wind Blox Pro for 7 rides during my testing, each time I found myself turning my head to the side, putting my ear into the wind, then back again, to truly realize what I was experiencing. It was fantastic. I could hear…cars, that’s the most important thing. I also heard cows (remember, rural Wisconsin). -- Best of Life Magazine
I could hear a car approaching me from behind at approximately a distance of 250 metres. Without the WindBlox, I certainly would not have been able to hear it until it was within 100m of me. -- Tyres and Soles
They go on easily, fit with most of the helmets I tried, and are pleasantly inconspicuous to onlookers. -- James Huang Cycling Tips
At age 73 my hearing has diminished somewhat. I ride on the street a fair amount so like to hear what is going on around me. I strongly believe that I am able to hear more with the wind blockers on my helmet straps. I will continue to use them. -- James Ralston
5 Stars! I believe the Wind-Blox is the perfect compromise between aerodynamic drag and noise reduction. The Wind-Blox was designed as a safety item. With great wind noise reduction, I strongly recommend this product, especially for the commuters. A true 5/5 stars!    -- Biketestreviews.com
I mainly bought these to get some wind reduction when listening to the radio (with earbuds) and they work great for this purpose. Up to around 20mph and in average wind speeds these are perfect!" -Amazon customer -- Amazon Customer