I’ve used calls from Kerry Carver’s “strictly business” set for going on 8 years now. The coaxer and open reed song dog slayer are my favourite. The raspy cottontail works well from a distance too. I always start a set with that coaxer which is super quiet, and Ive been surprised a few times by the dogs it can actually bring in. Carver calls are an unreal value, top quality too.
Another mouth call that doesn’t get a lot of recognition and another of my favourites is the Primos Cat Nip. Very unique sounds, and very versatile. I’ve never felt like I needed an E-caller, but I won’t argue their usefulness YMMV.