Ive shot the dart quite a bit even got second in a comp. I have a great time shooting it but only do it occasionally for fun. My big problem with it is that no matter how far away the animal looks you use your 20 pin and in my opinion that is bad practice b/c when you get into an excited situation you have a good possibilty to bring up your 20 pin and make a bad shot. Bad practice makes for bad shots.
But if it is a system like beltemag was discribing that would rock as long as it was accurate. Having to judge the distance and use the correct pin would be loads of fun, and good practice.