I have been and still am in the process of looking for the perfect EDC pen. As a lawyer I use my pen EVERY SINGLE DAY for hours. I have had dozens of pens, ranging from the classic, cheap pen, the Bic Cristal, to a few Retro 51 pens (which are junk and I refused to link to them), to a few different low to mid priced pens. I can't really justify a very expensive pen as the rigors of lots of travel and lots of court destroy just about everything (well, except for my Tumi bag which is just bombproof). A while ago I strolled into a local Staples and picked up a Zebra F-701. There is a lot of love for the F-701. A search on EDCF turns up dozens of pages of threads. Here is a typical one. The pen is a well made, simple design. Here is mine:
The body tube appears to be made of stainless steel with knurling where it rests in your fingers. The clip is super simple and though not too tough, it can be removed and repositioned, a huge plus in my book (the two previous Retro 51s that I EDCed broke at the clip, as did my Parker Urban XL Twist). It is simply a matter of unscrewing the retention piece, pull it and the clip out over the clicky, and then bending the clip back into shape and reversing the process. It can be done with no tools, which is great for on the go repairs. The clip is also smooth on the pockets.
The body tube is quite beefy, probably three or four millimeters thick. It can withstand a lot of abuse (having accidentally run over one, it was fine). Additionally because there is no lacquer or resin or wood to worry about I can wipe it down with a sanitizing wipe and it is nice and clean again.
The one problem I had with the pen was the CRAPPY refills. I hate black ink and after using a Fisher refill I can't go back (here is the refill I use, a Fisher Parker compatible refill, blue ink, of course, to distinguish copies from originals):
So I decided to mod the pen to take Fisher refills. It can take them without any modification, provided that you remove the tip guide in the nib of the pen. If you take the refill out and push it in the opposite way it usually goes that should dislodge the tip guide. Fisher refills will fit in now, but they will be sloppy at the tip and move a little when you press firmly to write.
To mod it, I followed this set of instructions. Instead of using an awl I used my drill press, using progressively larger bits to hollow out the plastic tip guide until the Fisher insert fit through with minimal clearance. I also had to cut of the end of the tip guide to make it fit. A quick pass on 600 grit sand paper and the tip guide looked factory finished. I stuck it back in the nib and reassembled the pen. Click, out comes Fisher refill, click again, in it goes. I could have hollowed it out more, but I chose a tight fit to prevent accidental activation of the pen while it is in my pocket. Now it requires a firm press, something that would be difficult to do by accident.
So for $12 ($7 for the F-701 and $5 for the Fisher refill) I have what is undoubtedly my favorite EDC pen. I am sure there are nicer pens out there, but this is a pretty hot combination and has stood up to about two years of abuse now without looking worse for wear.