Many of top Jazz players are particular about the taste of their own Wah-Wah sound. Imagine yourself playing a cool solo with your favourite Wah-Wah mute; it must look sharp, however, it cannot be achieved if the mute plays sharp: as most of the conventional mutes do.
If you are passionate about a harmon sound and are looking for a new, 21st century, quality/sound, try out the Wah-Wah mute. You will find why a lot of top Jazz players choose Best Brass.