I bought this pen because it was ridiculously cheap at around £12.00 Of course I’d heard about Noodler’s flex pens for years and it was a nice chance to see if it lives up to the hype.
Short answer is it doesn’t. Yes, you can flex the nib to obtain a pretty serious level of line variation but you have to press hard to do that. I mean, you could flex a shovel if you pressed hard enough! Also, it railroads a lot under pressure. That might be cured by a bit of adjustment but I’m talking out of the box, here. Such flexibility as the pen does display comes from the long slit in the nib.
It instantly reminded me of a small piston-fill Wality that I bought long ago. The whole pen is reminiscent of that other and the ink window is pretty much the same, as is the piston blind cap. That’s not a complaint, by the way. My little Wality has been working well and reliably for seven or eight years and like the Nib Creaper it was very cheap. My guess, then, is that this is an Indian pen, too. It may well be as durable as the Wality. Time will tell.
Forget about the flexibility for a moment and just judge the pen as a pen. The nib is smooth and it lays down a nicely wet line. It holds a considerable amount of ink. Visually it’s no great shakes but it isn’t ugly either with its red and black pattern. The clip is nicely springy and should work well. The barrel and cap threads are cleanly and deeply cut. They won’t be wearing out in a hurry like some of the cheap pens of yore. It all works as it should. I would say that for value for money it’s unbeatable and it’s the kind of pen you could carry or leave lying around the desk without much concern.
The downside is that it’s quite small, even for my not-very-big hands. Then there is the fact that it’s marketed as a flex pen and in practical terms it’s a semi-flex at best. The railroading when flexing is distinctly annoying. That’s the kind of thing you should take care of at the design stage. With a multi-finned feed like this one it just shouldn’t be happening.
These gripes aside, it’s an almost unbelievably good deal. A piston-filler that writes well for £12.00? You can’t go wrong with that!
Goodwriterspens's Blog 
I think it uses a No. 2 nib, so it could be the ideal home for a spare older nib.
Spare older nibs are a rare resource. If you have an older nib that needs a home, give me a shout. I’m always looking for nibs.
I consider myself quite experienced with Noodler’s flex pens. As such, I agree with pretty much everything you said about the Noodler’s Nib Creaper. But don’t let the crummy little Creaper lead you astray. There are wonders just over the horizon.
Two of my favorite pens in regular rotation are an Olive Ripple Ebonite Noodler’s Konrad, and a Mandarin Yellow Noodler’s Ahab. Both of these Noodler’s pens have modified #6 nibs to enhance flex and hacked feeds to keep up with the required flow.
It did not take me long to initially hack the nibs and feeds. But fine tuning the feeds was a process that occurred over a week or so of regular use. Heat setting the feed also helps. Even with the flex modifications, once the feeds were tuned the pens have proven to be reliable consistent writers.
Here is a thread on the FPN that discusses the added flex modification for the Noodler’s Ahab and Konrad – which have interchangeable #6 nibs and feeds:
http://www.fountainpennetwork.com/forum/index.php/topic/240492-noodlers-ahab-ease-my-flex-mod/
One you modify them, the only seriously bad thing about these two pens is that spare flex nibs and ebonite feeds are not available for them. However, in a recent online interview with Brian Goulet of Goulet Pens, Noodler’s Ink Founder Nathan Tardiff said spare parts for the Ahab and Konrad are in the works.
Your comment will be useful for any of my readers looking for a modern flex pen. I’m not. I buy the occasional modern pen when curiosity gets the better of good sense. My interest is really in pens made before 1965.
I’m very late to see this, but wanted to say that it’s nice to see a bit of positivity about these modest little pens for once. Most pen enthusiasts seem to go out of their way to express their contempt for them. In my experience they have a jaunty writing action, are a doddle to strip down for cleaning, and provide endless amusement when it comes to getting the nib and feed set just right. A very handy item to have around if you have an ever growing collection of ink samples and don’t relish the task of flushing lever fillers. Not, however, any sort of replacement for a pre-war pen and a bottle of Waterman blue-black.
I hope, Andy, that you are not suggesting that there is snobbery in the pen world! I couldn’t imagine such a thing! I agree with you that there’s a lot to be said for these pens – perhaps a lot more to be said for them than there is for many other pens which cost a multiple of what you would pay for the Nib Creaper. I had a lot of fun with my one, before I set it aside. Good as it is, it’s not really my thing.
Heaven forfend. The Creaper really comes in for some bashing though, poor little thing – including some, ahem, sniffy comments about how it smells.