I think I'm strangely allergic to one of them but haven't really figured out which...prime time is my best guess. I've always found the E-Z comb adhesive handy to have around....
Tail glue is pretty awesome for hair that isn't so cooperative and it has excellent hold. Prime Time is really good for calves that you don't paint. Easy comb is good for like sale calves where they're gonna be up for a while so you don't want a real heavy glue in them.
Like sj89 says, different products for different hair, different weather, whether or not you can paint over it, how long it needs to last, etc... Some good products here, too. http://www.blueribbonshowsupply.com/grooming_products.htm
I like a light natural spray but I have found that different hair types & the weather really affects my choices. I do know I don't like the black adhesive.