I have and use the Phantom Predator call. I found I needed to add a daypack of somekind to carry it in as the speaker is a bit large to hand carry as I hike into where ever it is I will be hunting and the speaker wire is a mess to deal with if you don't have some way of winding it up.
Sometimes I get the feeling I'm blowing my cover when I am setting the speaker out and playing out the speaker cord.
Some of the sounds available on the call are not "natural" to my Wyoming enviroment (we don't have too many squealing piglets here-about) and the crow call is a far cry from our ravens or magpies. So those sounds are a waste for me.
Other than that I like it. But nothing beats fooling them with a hand call!