I have tried the ground sheep (mutton) and the ground rabbit and both went over great here. I just use it in my rotation. I partially thawed it out and then sliced into patties that went back into the freezer. Then just take it out and feed, very easy and convenient, like the pre-mades you buy. I believe these are whole animal carcasses, minus the stomach/intestines, so it is meat/bone/organ in about the right ratio since it is an entire animal that is ground up.
I agree with Chili that whole meats and meaty bones are great for teeth, while with ground - some dogs just suck it down. But I do think they have their place when used in rotation with whole meats and bony pieces.
Some dogs are resistant to eating organs. These grinds are a good way to get organs into them with less stress than 'forcing' them to eat their organs. They are easy and convenient for travel as well. Hare Today has a great variety as well and its fun to try novel meats that may be hard to find such as rabbit, llama, goose, etc.
Oh, and if you have a chance to order from them - Brody says to be SURE and get some ground green tripe. He says it is DELICIOUS.