The guillotines are whicked and very effective, but only at close ranges such as a max. of 25 yards, IMO! They are noisy in flight, and they require you to use longer arrows than you would normally use. Those 4" heads don't fit well in the normal broadhead quiver hoody either. And if you practice with them, you'll ruin the blades, almost gaurantee that.
I shot my bird last spring with them, and there's no tracking after the hit. My buddy shot two birds last spring with them, on the same stand. Neither bird went any where.
We'll probably be using them again this year.