I've spent more money than needed over the years on tape and solid state calling systems. Some are better than others, but none have proven to be 100% realistic. My best example is this. Right now, if I go hunting and my hawk catches a rabbit, the rabbit's squeals will call in every songbird, cat, dog, crow, raven, ect in hearing distance. I have to get there quickly, or my hawk might end up as coyote or eagle food. It's the real thing. If I sneak into the woods with my latest wizbang calling unit, and play a dying rabbit, I may get a crow to come by, or a cautious coyote but the response will never be as dramatic as a real injured rabbit, or disbudding a goat kid.
What electronic calls have you found to elicit the best response from wildlife when you use it?