Well, sometimes a young pullet will have a couple of long tailfeathers, too, but they molt out. So, I never go by that. Going by saddle feathers and a wide comb on an EE will usually give you the sex of the bird. Hackles aren't as dependable since many hens look to have pointy hackles in the EEs.
I was looking at some photos of BO hens on google last night and noticed that their combs and wattles get pretty red! This is how I had been determining sex on my BO.... now I'm not so sure any more. We will start putting unwanted roos in the freezer in the next month or so... I don't want to butcher any of my pullets by mistake.
Width of comb... something else to look at. Think I'll take my camera to the coop/run with me and see if I can get some photos of my potential roos and get some opinions.