So I went for a fairly long drive today, trying out the whisper strip for the Shoei helmet. The weather was perhaps not perfect for this test with 25 degrees (Celsius that is) and extreme humidity, but it still give some useful results.
Having the strip attached to the bottom of the helmet keeps all moisture trapped inside, which easily leads to the visor getting fogged up. Some of it may just be the result of weather conditions, but it’s an important thing to keep in mind on long trips. Using pinlock is almost a necessity.
Sound wise it’s both ways; it does dampen the sound of the wind quite well. Of course not as well as using those standard yellow earplugs, but still good enough. The downside is the humidity I mentioned above, and that one looks like an untrained monkey when trying to push the head through the strip.