if you are hunting unpressured dogs any will work. i cant even begin to count the number of different calls i have used over the past 15-20 yrs to call them in. however, as more and more people educate yotes in our area, i try to constantly rotate and incorporate new calls with different pitches into my arsenal. the one i killed today came to a new split reed widowmaker call. It is a little higher pitch than i normally like, but it is a unique sound that a youngster couldnt pass up.