ianwood said:I guess I am "hung up" on the relative simplicity of it just being a bent up wire hanger from the dry cleaners.
Hahaha.... I completely get that.... you can make a perfectly good antenna out of a wire coathanger as long as the wire lengths and angles are as perfect as you can make them.
For real world comparison, well as I say, I've got a box full of cheap ones that are useless and a relatively expensive one fitted; I know I'm not the only one. The proof is in the pudding, I get far better results with the more expensive hardware than I ever did with the cheaper chinese antennae. A quality hand built antenna clearly will cost more than mass produced rubbish. I'm sure if you have a flick around on google you can find the data you are after or you could just contact the antenna guru himself (http://fpvlab.com/forums/member.php?67-IBCrazy)... he seems pretty helpful from posts of his I've read.
There is masses of info out there about this. As I said in a previous post, you will find the odd cheap ones that are perfectly suitable however I think in general, most cheap ones aren't.