This year I started shooting the Grim Reapers after many conversations from good friends of mine that have been shooting them for years. These guys have shot countless elk and god knows how many other animals with Reapers and they have always been impressed by them. I shot my antelope with one this year and the entrance wound looked like a rifle exit wound, I was sold right there. one of my good friends actually wanted to make his own broadhead and bring it to market, that idea forced him to do alot of testing into ballistic gelatin and he said the reaper won hands down against all other broadheads. Now i wasn't there when he did any of the testing but he has photos to prove it.
I think when it comes down to it though there are a couple of things to think about.
1- are the blades SCARY sharp.
2-Do they fly/tune out of your bow and
3-Do you trust them.
Some guys just don't trust a mechanical on a big bodied animal like a elk where some guys have 100% confidence that a mechanical will put a elk down. For now I believe in my Grim Reapers and have faith that they will put a elk down if I do my part by making a good shot.
Just my 2 cents.