Hi,
Well, I would never characterize this brief post as a full-blown "review." That said...
I acquired one of the modern chased black Crescent Fillers, used, a couple of weeks ago. In my world, that's barely long enough to get a pen flushed out, inked up, and into the rotation. So please regard these only as preliminary reactions.
To my eyes, the pen is a reasonable facsimile of the original (albeit not the "exact replica" touted by the manufacturer). It's resin (celluloid?) rather than hard rubber, but the chasing is well executed. The sterling furniture is nice, although I could easily dispense with the engraved Mark Twain signature - just a personal quirk. Overall, the pen definitely comes across as a high-quality, well-executed product.
One respect in which the pen most closely resembles the original crescent-filler models is in its weight; although it's large enough to be classed a full-sized (even oversized) pen, it's light and fatigue-free in use.
The large two-tone nib is attractive, and it's a fine writer: not "flexy" in the vintage sense (what is, alas?), but definitely "soft." In fact, I think that adjective may suit this nib better than any other I've tried. It delivers a welcome combination of suppleness and springiness. It's definitely possible to produce modest line variation with it. One quibble: my specific pen occasionally requires half a stroke before starting up. I'm not suggesting that this issue is common to the model, simply because I bought the pen second-hand, and I don't know anything about its previous life. I suspect that there's a fraction too much space between nib and feed, and I expect that I will eventually have that matter attended to by one of our distinguished restorers/nibmeisters.
Once the nib gets going (and I certainly don't want to overemphasize the start-up issues!), it's wonderful: remarkably smooth and lively. Ink flow is generous; if my pen is a representative example, fans of dry-writing nibs might want to look elsewhere. My nib is denoted a medium, and that seems about right; I've got finer mediums in my collection, certainly, but this isn't a "broad" by any means.
As for the filling system: it's actually very enjoyable to use. I can understand why lever-fillers and button-fillers might have seemed, back in the day, more "advanced" than the crescent mechanism: the crescent does protrude from the barrel, and 1920 eyes might have seen it as ungainly and antiquated, to say nothing of its potential for catching in a pocket. In 2007, however, the crescent system seems like an endearingly anachronistic, charming novelty. (In the 50s, likewise, the advent of the Snorkel must have seemed miraculous to folks weary of wiping off sections and nibs; but for me, here and now, the Snorkel seems unnecessarily fussy in comparison to its predecessors.)
On the other hand, there's nothing anachronistic (endearingly or otherwise) about the crescent filler's efficiency. I seem to remember that Conklin advertising, way back when, used to talk about the performance advantages of its system (and online pen reference sources make reference to its mechanical superiority as well). This may sound odd, but I think it's possible to "feel" the crescent system compressing the inner sac more completely than other mechanisms. The tactile feedback (as the sac is compressed and as it fills) is very direct.
One minor point of interest (a function not of the pen's design, but of my lack of an instruction sheet): I didn't realize, when I first used the CF, that the rotating ring for the crescent was designed with a locking feature. (I have a few unrestored vintage Conklins, and so far as I know, those rings stay put strictly by friction.) The modern ring, I discovered, rotates much more freely, and I found myself wondering how one might keep it from rotating into the unlocked position in the course of a day's writing. Well, that's easy: simply slide the ring forward or backward on the barrel, and it will lock in place. A thoughtful improvement, I think, on the original design.
To sum up: I actually like the CF a whole lot better than I expected. The hands-on experience of using the filler seems like a powerful, living link to early fountain-pen writing. Don't get me wrong: I own lots of vintage pens, and I love 'em. But in using one of them - even a NOS or perfectly restored specimen - one is conscious of using an antique. Using the modern Conklin is different. Because the pen is new, the experience feels much closer to the experience the original owner enjoyed writing with that antique...back when it was a daily workhorse rather than a museum piece. By rights, it should feel less authentic; but it actually feels more authentic (just my reaction, of course).
So: reliable performer, enjoyable filling system, practical everyday pen, high build quality, lovely nib...and a generous helping of history, to boot. I wouldn't hesitate to acquire one, if the right opportunity presents itself.
Cheers,
Jon