I hear a lot of people bragging about their "homemade J.I.C tube" but yet nobody has posted theirs when asked. So unless someone can post theirs and the price paid for all the parts, they need to bring it down a notch. Compare the price paid for a pistol grip 500 and a pistol grip J.I.C setup and the price difference is very little.
Anyone who creates one from scratch, please post pics of yours with cost analysis and make sure it contains the survival kit, 2 large zip lock bags (3 foot and a 4 foot), tube, locking device with wingnutt, 2 styrofoam pieces and the sling. I'll even forgive the decals. Of course, it has to fit a pistol grip shotgun as well.
If you can't do that, you need to move along. Instead of talking about it, do it and prove it.