I used it all the time while driving with my Droid Charge, but it's useless now. And I drive a damn Cadillac that is very quiet, and even when turning the fans/radio completely off, it still doesn't work well.
It does work well (most of the time) in a completely silent room, but that's hardly a common scenario when I need to use it.
And that "does this top need to soak for a week?" just worked perfectly when I tried it. But I couldn't get it to work in over ten attempts before. And I bet it magically won't work an hour from now. The inconsistency is painful.
I'm still adamant that something is wrong here. There is no way this Samsung Galaxy S4 should be blatantly inferior to my 2+ old Samsung Droid Charge.