The Weckl muffler is excellent sonically as it doesn't muffle the entire head, but only the base of the head. You can adjust the dampening by moving the clips provided back or as close as you like from the head.
The only issue with the product, is that adjusting the muffling can be annoying if you want to do it quickly, as putting your hand through the port hole to make the adjustment can be tedious, unlike the Evan's eMad or the Thon Rock pillow which requires no clamps, only velcro.
In transit, the clips may pull away from the velcro strips, which is something that has happened to me many times.