The only calls I use are the Primos Palate Plate diaphram calls. (I think they are called "Sound Plate" now). In particular the white one (Ivory I think it's called). IMHO they make, by far, the most realistic cow calls and they allow you to manipulate your bugles. I used to use an E.L.K. Power bugle and it makes a big loud beautiful bugle. But in my experience, this isn't what works. The diaphram call allows me to sound as big or as little as I want on my bugles. They do require a little more practice than the hand calls though but well worth the effort.

"What we do in this life echos an eternity"