This is by far the most economical target out there. Only downside is that broadheads will slice right through.
You might consider picking up heavier plastic sheeting for your stuffing. I get mine from the local discount furniture store. They are happy to give it away. In my experience, shrink wrap tends to cling to arrow shafts, where the heavier plastic doesn't. Makes pulling a bit easier and you never have to thumbnail plastic off your arrows.
Also, watch for the smaller feed sacks and grass seed bags. Fill these and fold the end over a 50' piece of rope, then wire tie the flap into place. Carry the end of the rope into your practice tree stand and you can retrieve arrows without having to climb up and down all the time (as long as you don't miss, that is!).