I've used Sow in Heat succesfully before. IME, the trick is to get fresh stuff and keep human scent down in the area where it is. In an effort to do this I took a nutter arrow and wrapped the end in yarn. When I got to where I was sitting I dripped some SiH into the yarn and shot the arrow into the ambush area. That was there's no fresh human scent there.
That said, the biggest one I killed with it came in from directly down wind. He was obviously skeptical and smelled me but after about 30 minutes of him sticking his head out, getting spooked, throwing a FIT in the brush then sticking his head out again the little brain finally overruled the big brain and he came out to the clearing to check out the scent and got smacked.