Realisticaly there only good as cover scents. Elk have a lot more area they cover then a whitetail, and whitetail are more terriotorial. I have used pretty much every scent out there and the only time i notice a difference of using it or not, is if I'm in a bad situation where I'm up wind from the herd. I use an elk bomb to hit any scrapes and rubs in the area, but can't tell that the elk frequent it more often than ones I havn't sprayed.
your best bet is to use a little for cover scent maybe some scent eliminator also. Don't buy into the gimmicks too much(like myself has in the past). If elk are in the area just rub some fresh elk crap on ur boots and your good to go, cheaper and as good as any scent out there.
Like AA said it doesn't seem to attract them a whole lot but works great as a cover scent. I especially like to use them on my boots when archery hunting. An elk is as good as anything out there at crossing your path and smelling where you walked, then bolting right back where he came from. I step in every pile of elk poop I can find when I'm out walking in the elk woods.
I also like to use the elk scents as cover. When i sit on a wallow or a set-up for a bugeling bull coming in to a cow call i will spay a couple of bushes near me for cover scent. Heres a picture of a pine tree i sprayed with a scent called Elk Fire by wildlife research( that i use the most), and a small 6x6 thrash it where i sprayed, while i was sitting on a wallow.[img][/img]
The record books, that are put out by Boone & Crocket and Pope & Young and where I live is Henry Kelsey they are a great way to research a state or a province for big game. This does take some time but the knowledge it gives you, can be very valuable. Not all hunters have their trophies recorded, as where I live after the Hanson Buck became the new world record typical Whitetail, we saw a flood of hunters and now that has happened, some hunters are shying away from the record books but...