If you want to do any crow or snow goose hunting, the Super Snow-Crow Pro is a beast. It also is awesome for predator hunting too. It will be the last E Call you will ever buy. If you never intend on going snow or crow hunting, the Hell Fire is good enough. You can't go wrong with any call they sell. You truly get more bang for your buck as you go up the price range on their stuff. Customer service is top notch as well.
Just a warning, if you buy the Super Snow-Crow Pro, you will start getting free invites from people you never knew were your friends....it is that great of a call.