Yes Sir!
Waste of money. Can't see any Law Enforcement issues with a SBR or Suppressor. An AR Pistol is almost the same as a SBR but no Stamp. There is a "Forearm Stock" If attached to your forearm - it is a pistol, put to your shoulder and it becomes an SBR. Look at all the Glock conversion kits that just skirt the NFA-ATF regs.
In hind sight wish that I didn't build it, but it is cool to shoot. I would carry it all the time in my truck when checking out hunting areas of filling the hog stations. When I would walk Samson on back roads, I would bring it along in case I saw a Yote. It is a Keltec PLR-16. The stock and front grip and can be taken off and then is it considered a "Pistol".
Federal Law 27 CFR 478.11. Handguns have a short stock and can be held and fired with a single hand. A rifle is a weapon intended for firing from your shoulder. Short-barreled rifles have barrels under 16 inches long or have a total length of under 26 inches. This includes collapsible stocks when fully extended unless the stock can be detached..
However, be aware that if your handgun winds up firing from the shoulder and doesn't conform to the 16-inch barrel-length requirement or 26-inch overall-length requirement, you've illegally created a short-barreled rifle. As such, it would need to be registered to the ATF and taxed first.
Now, if you add a vertical foregrip, it gets into murky territory. It's neither designed to be fired from the shoulder nor with one hand. The short answer is, it falls into the category of "Other" and has to be registered.