I'm like you, never really used them, 'cause I've never had much confidence in them. But, many guys swear by the "True Talker" call from Hunter Specialties. Also, guys like "The Can" estrus bleat. I bought both, figured I'd try them out this year. Last time I was hunting, ~3 weeks ago, I had 2 does within 20 yards of me. There was no shot, too much brush in the way, so I figured I'd try the grunt call and see how they react. I blew a few grunts, they heard it, but reacted in a neutral way. All they did was look in my direction, then continue slowly browsing through the bush. I guess they recognized it as a deer call, but it did not cause them to be scared or curious. A buck would probably have reacted differently.
-Sean