Most people are awestruck when they see it for the first time.
It is big, bad, and ugly. I think the most common thought I hear when showing one to somebody who has never seen it before is the suffering the Zulus who were shot with this cartridge must have endured if not killed outright. Nowadays, there are two sources for this cartridge, Old Western Scrounger in Montague, California, and 2nd Amendment Research and Development Corporation in Gleeson, Arizona. OWS specializes in making obsolete cartridges, and the .450 Martini is one of their best sellers. They're made from 24 Gauge CBC brass shotgun shells which they resize to the correct dimensions.