I dont think they are really necessary. I have had turkeys walk within feet of me wearing realtree or another popular brand of camo. I think the main thing is motion. Turkeys will catch motion very easy. Thats the easiest way to get busted. Fubar
I have a Ghillie, and use it for turkey hunting. I also have the 3-D suits. The 3-D suits are more convenient (less bulky and cheaper).
Many people built their ghillie themselves (myself included), so they want to see how well it works. It takes countless hours to tie the 8-10,000 knots, so a lot of people figure they might as well use them. If I would have known how long it would take, I would never have started it! It does look great though.
In the heat out here in the west the ghillies are murder.
A couple of years ago I was sitting on a ridge near San Diego in early morning fog so thick I couldn't see 20 feet. My buddy had seen a cougar hop out of a tree earlier and I was a bit jumpy sitting by myself on the same ridge. I kept hoping the fog would lift because I could hear turkeys gobbling but I knew it was a lost cause to call in the pea soup.
About that time I see this bush moving toward me out of the swirling fog. I rubbed my eyes and pulled the shotgun up into port arms. At first I thought I was imagining the movement and then I saw it move again. By now my heart is pumping and my mind is racing. What is it? Another cat? I couldn't make out any form or shape but I knew whatever it was, it was closing on me pretty fast.
I got the shotgun up and snicked the safety off. It never dawned on me it was another hunter because I didn't see the outline of a person and it was close enough to see a face or shape of a person. Right then the guy yelled and I put my shotgun down. The guy had on a ghillie and was lost and had heard me yelping and came over to see if I was a hunter and whcih way to the road.
I felt like an idiot for pointing my gun at him and realized I should have yelled first to see if it was a person. He wasn't upset and headed off toward the road. I changed ridges that afternoon. That's the only guy I'e seen hunting with a ghillie on out here in the west.
I imagine they work good when set up but walking through briars must be a real pain with one on also. I tried that 3-D camo stuff and it was a real test of stamina to go through any briars with it on.