I take both,if I don't take both I take mouth calls. For tight cover I like an electronic. I'll use one in open country too though. There are a bunch of sounds I can't make on a mouth call and if it's windy I can turn the volume up on an e-call. But I can't say I notice too big of a difference when I use an e-call or a hand call as far as numbers go. Coyotes don't think like humans. We can tell a difference but I think if they have a bad experience with a "rabbit" they're going to be leary regardless.

I don't just play one sound on a stand generally. Very rarely do I so I'd rather have a bunch of sounds to choose from. What time of year it is has a lot to do with that too. I've developed my own system for calling that seems to work well for me that I base off of the areas I call and when I'm calling those spots.
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I didn't climb to the top of the food chain to eat carrots.