Worked great for my cribber but in combination with other things - 24/7 turnout, plenty to eat since he was starving when we got him, ulcer meds, electric fence, a quiet companion. The Miracle Collar had to be pulled so tight he would bloody himself.
Glad this topic came up. I have been using a french style cribbing strap while my mare is indoors, but have been afraid to turn her out with it on, despite 24/7 turnout w/ shed & companions on 10 acres, she will deliberately hang out in the shed alone and crib incessantly. Been considering purchasing a dare collar.. the french style one is cheap and curbs the habit, but it doesn't stay in place so well and needs to be tightened, her attempts at flexing her next stretch it out.
Not familiar with this one, but the most effective collar I've used is just a plain wide leather strap. No rubs and stopped the cribbing with a looser adjustment than the others.
The Dare collar is basically a thick harness leather strap with a tapered block that tightens when the horse pulls back. You can leave it looser and it only tightens when they pull. When my TWH grazed it was completely loose.
We also eliminated any spots that he could crib on - we covered wood edges, never left the dutch door open, strung a hot wire above gates. We also had to make sure that hay was available before he finished eating or he would look for something to crib on.