For home defense, a pistol grip, "sawed off" (can't be shorter then 18" without special ATF permit which you will not get) pump.
It really isn't good for much else besides that type of a conflict
I realize that the number one goal would be to survive an unwanted conflict, but keep in mind, the next big concern will be staying out of jail!
I don't disagree with the effectiveness of creating mayhem that this weapon has, although such devices are often credited with the ability to "kill on both ends", one has to be confident that the presentation post incident proves palatable to the point of innocence on your part. Therefore, I would recommend selecting something commercially available, at the typical sporting goods store, deemed reasonably acceptable by the norm vs. the hacksaw special with "KILLER" hand-carved in the grip!
Even if there's no real-time recording of the incident, someone is going to paint a picture, this often being of the median and of a depiction preferred by the creator, so the less ominous you present, perhaps the less quickly you will be condemned.
For example. to the best of my very limited knowledge, I am not aware of evidence stated at this time that this current debacle although constantly stated as being result of racist provocation actually was. Perhaps, this is actually just the result of a criminal, irregardless of race, resisting arrest to the point of requiring multiple officers to subdue him. Lesson is that is probably best to avoid the impropriety that draws the attention of law enforcement in a negative view; and for the police as well as not to provide the media with any angles to exploit for their own agendas.
Remember, the world is run by the stupid people, like it or not, but believe it!
Scott.