For me, it's a winner! After watching Brian Goulet's videos on how to clean, disassemble, and tweak your Noodler's pens, I LOVE my regular flex pens too, but the only drawback was how quickly I ran out of ink when sketching. Flex nibs just DO use more ink, that's the nature of the beast...and the smaller Creaper Flex pens don't hold much...
Ahab DOES. I filled it before I left home, spent 5 days in Nevada sketching, and still have a pen that's over half full (I got the clear demonstrator model so I could keep track of that!)
It has a pump action, and when you fill it, both sections fill up. You can see I didn't use very much of the main section, only the ink in the pump itself.
Brian Goulet gives excellent customer service and answers questions promptly...he's made a number of videos that clearly explain all the details. Check out their site HERE.
I love being able to take these pens apart, tweak them, completely clean them, etc.--I'm delighted not to be afraid of my pen! They're inexpensive enough that this is a real boon, as well. (With some of my other pens, the Namiki, for instance, I'm afraid to take it out in the field, and the antique pens I send out to an expert to be serviced. SO nice to save $40 or so and just be able to do it myself.
I'll admit I wasn't sold on these pens at first...once I learned to clean and adjust them, I couldn't be happier. And they're $14 and $20 pens!
These are only a few of the sketches I did, by the way!
I test drove it for flex against several of my other pens...the Namiki Falcon at top, my antique-but-temperamental Waterman 52, the original Noodler's Flex, and the Ahab at the bottom...they're all pretty comparable (though the Namiki doesn't go as fine), and I don't have to push too hard to flex.
You DO have to slow down a bit on the Noodler's pens when fully flexed or you bet some railroading (double lines), but they're very versatile and so far very dependable!
Both the paper and the ink you're using make a difference in how these pens perform...or ANY pen, as far as that goes. I've found Noodler's Lexington Grey to work best for me. I bought the new brown formula ink, and was disappointed that my Ahab wasn't pleased with it...it didn't want to feed well. I cleaned the pen thoroughly, loaded it with Lexy Grey and it performs like a champ.