Every year or two it seems like the manufacturers come up with the latest and greatest new cartridge. Some make it, some don't, and some end up as zombies (still around, not widely adopted or available). It looks to me that 6.5 Creedmore, for example, is popular enough that it has made it and will continue to be available for the forseeable. I hear enough mention of it and enough manufacturers have come up with rifles, ammo, components, dies, etc. Other than really, really clear examples like this, how do we know a cartridge has made it? The genesis of my question is that I like the idea to 350 legend, but I am not eager to join the parade until I know this will not end up being an orphan.