I use Hunter Specialty's owl hooter and a coyote call. I called in an area where I expected to find gobblers with my owl call and herd nothing
on my way back I used the coyote call and boom they sounded off right where they should have been.
I've located gobblers on the roost with my owl call, set up and here comes another hunter using a crow call several times but the gobblers did not answer. So at least in Colorado I would say owl and coyote calls are more reliable.