Eightbore,
Let me get this straight-my Darne is going to remove the fired cartridge, with it's now separated base, lay it in my hand, just like it always does, and I am going to pocket the thing, just like I always do, and not notice the 'coupla inches of plastic missing from the base?

Do you know how Darne ejectors (not a good word, for this application, really) work? Are you sure? Because it sure doesn't sound like you thought about that statement very hard.

I save my empties, but not to reload. I don't leave clutter in the field, regardless of gun type. The English CIP cartridges I've used for several seasons (say, about 20) don't seem to have a huge problem with separating bases, bloopers, or what-have-you, in my humble experience. Can't say I've spent money on promotional loads, once fired anything, or old ammunition, myself.

I'll be sure to keep an eye out for it. In the meantime, perhaps you might consider better quality ammunition for use in your stuff? Just a thought. You know, a very highly regarded English gunsmith here in the states considers the American penchant for reloading, and the home reloading press the key to his survival and prosperity, by supplying a never ending stream of Fubar-ed barrels on double guns for him to repair. Nothing like putting the money where one's mouth is. Good for him, eh?
Best,
Ted