Spoiler alert: this may very well be my favorite compact fountain pen.
The Rook is designed for pocket perfection. The aluminum body is so lightweight, you might mistake it for plastic (I had to bite mine, like a pirate with a suspect gold piece, to make sure it really was metal…it seems like metal….you’d better buy and bite one yourself, though, just to be sure). It is the shortest fountain pen I own, by 0.4 cm, shorter even than the Kaweco Liliput, which JetPens STILL erroneously claims is the “smallest fountain pen at JetPens that accepts standard international short cartridges”—the Rook accepts standard international short cartridges and by JetPens’ own measurements is shorter. But it’s also much cheaper; perhaps that’s why it isn’t getting the recognition it deserves?
Sleek and durable body, has a clip, easy to open (once you figure out, after a comedy of frustration, to hold the black end part on the non-clip end and pull away the rest of the black body and clip end), snaps securely shut, and when posted boasts the useable length of a full size pen. And it’s sturdy. This is what a pocket pen needs to be: quick and convenient, for ease of use, but also sturdy and reliable, otherwise it wouldn’t be worth using.
It’s not my favorite nib on a compact pen—my heart belongs to Kaweco on that score—but it’s still a good nib. A little on the dry side (especially compared to something like the A. G. Spalding), the nib is more tactile than smooth, but it’s never scratchy. Ink flow is good, unless I let it sit for a month or more without using it.
What matters is it does what I need it to do, without any notable problems that would get in the way of writing, and the design is comfortable enough that I could write for an extended period of time if I need to. Be warned though: the barrel, as you can see, is a bit slim; if you find thin pens uncomfortable then this might not be the pen for you.
My only complaint against the Ohto Rook is that the red band around the clip area isn’t the same shade of red as the grip; the clip-band is just a little lighter, perhaps a fraction more orange. But for such a great pen, that’s pretty nitpicky stuff.