With closed reeds you do not have a lot of control over the pitch of the call. Other than varying the amount of back pressure you are pretty much at the liberty of the tone and pitch of the reed. With open reeds you have a lot more control by varying the position of the reed in your mouth. It is real easy to go from an older deeper sounding dieing rabbit to a young higher pitched rabbit. You can even use an open reed as a howler in a pinch.
There area lot of really good youtube videos on how to run each type of call.
My closed reeds run $30 and my open reeds run $35.
