Conklin Crescent Versus Endura

[sidthecat]

Now heres an interesting thing: I was looking at a Conklin Crescent on eBay - a pen I find fun to use and often with very flexy nibs, and I happened to notice that the later Endura line - with a more conventional filling mechanism and less extravagant nibs - seem more desirable pens, as expressed by the listed prices.

So Im intrigued: what is it about the Endura? I have eccentric tastes and my fancy runs to ringtops, but the Crescent is an older, rarer and odder pen, which usually adds value.

Anyone care to hazard a guess?