Hey Dave,
I have one of the Rancho Safari ghillies (bought it used for $100). It is the pants, top and boonie hat type of set. It is made up of strips of non-cotton (or cotton blend, definitly not 100% cotton) camo cloth. I am pretty tall so the jacket is not as long as I like, but it works just fine.
The non-cotton cloth doesn't soak up in the rain too bad. As far as effectivness, I think it is hard to beat. Even compared to a blind.
I have several spots in the woods where I hunt, that I already have a few dead branches stacked around to sit in. Not a full brush-blind by any means, just a good spot with some front cover and a backdrop. I have done well with this set up.
Here is a picture of my suit in action. This is actually my niece. We were taking turns wearing it and doing a little hide and seek.
We have one really large field (80 acres) with several little wetlands in it where we hog hunt and shoot a few ducks. The grass is anywhere from knee high to over head high and the outfit works well there too.
I have a buddy who bought one of the cheapy string material type of ghillies, and he wasn't to happy with it (I think it is made more for wanna-be paintballers). It was sparsely made and the jute string is heavy dry, and unmanageable wet.
Guess what all the rambleing adds up to is, they work VERY well for me. I managed to luck into a very high quality set for a good price. After having used one for 3 or 4 years now, would I buy one for full price? Knowing what I know now, you bet!
I think the Rancho ones are the best quality, and (I think) they actually make the Cabela's brand. Another buddie bought the 3/4 jacket so he wouldn't have to mess with pants and has really liked it.
Hope this is type of info you wanted.
OkKeith