I had a favourite fountain pen for years - it was one of those cheap Sheaffer ones they used to sell in the stationery aisle in grocery stores. They were the thin-barreled ones, not the thick ones like the calligraphy type; available in Fine and Medium nib, and in a multitude of colours. My favourite of all of them was the transparent purple, but the clear one was great, too. I lost my last one a few years ago, and realized they were no longer selling them in stores. I searched online, and discovered they seemed to be completely gone. There were Sheaffer school pens, but these were thicker and because they didn't have the metal band around the threads, the body was less sturdy (I've cracked at least one from screwing the nib into it too far). And they don't have transparent bodies - just a window to see the ink through. The red pen in the picture is the new one. By the way, both types of Sheaffer pens use the Skrip ink cartridges, which come in a whole bunch of nifty colours (though I think some of the cooler ones (grey, burgundy) have been discontinued...). The nibs have a rounded end, and work equally well for both left and right handed writing.
Here's a writing sample with the newer Sheaffer pen - nice smooth flow, no scratching on the page, etc. (The colour is very muddy, because I recently switched a black cartridge out for a burgundy one, and it's... well, I didn't clean the pen first. Until recently, I was totally unaware of fountain pen maintenance -- those old Sheaffers used to get new cartridges whenever they ran out, and I never cleaned them before switching!)
Fast forward a few years, to when I learned of JetPens.com, and the discovery of the Pilot Petit 1 fountain pen - an absolutely adorable Japanese fountain pen that costs hardly anything, comes in about a dozen colours, has a transparent body, and has TONS of ink colours...
...in very specialized cartridges.
Again, rounded nib = great for both lefties & righties. Cute size (I can carry it in my pocket!), and oh, the colours. How could I go wrong?
Yeah, that specialized cartridge.
It seems that Pilot is discontinuing production of the Petit 1*, and therefore, the cartridge is no longer needed. :\ No converter will fit, and the size/shape of the connection between the nib and cartridge means that no "standard short international cartridge" will ever work. *sigh* When I use up the last one, there are no more. Thankfully, like a good addict, I bought a good number every time I made a JetPens order. I'm planning to save some, and fill them from bottle ink & see how long they last with multiple reuses, but at some point, I'm sure this pen will end up obsolete for me, too. *has a sad*
So, yay for JetPens.com - again, like a good pen addict, I also bought a Platinum Preppy pen (see the clear & purple pen in the photo with the red Sheaffer). It's another cheap Japanese fountain pen, but unfortunately it doesn't have rounded nib (this is the 05 -- I got an 03 later, and it does - yay!) Sometimes it has some poor ink flow issues, and sometimes it's a bit scratchy (for example, see the underlines and how they skip at points.)
But, it's a pretty good pen for the price (cheap!), has a purple accent version, and... well, *sigh* it uses specialized ink cartridges...
I did, however, discover that Platinum also makes a converter that will allow the pen to use the "standard short international cartridge." I just had a hell of a time finding one, though - JetPens is out of stock, and I got scared I'd never find one, so I Googled and found Cult Pens in the UK - they have them, so I grabbed one. Also ordered a box of assorted Diamine ink cartridges to use in it, because they have some pretty awesome colours. I'm hoping that the ink plus the converter will alleviate the ink flow issues, and this will become my new favourite fountain pen. It doesn't seem to be a left/right hand issue, so I'm keeping my fingers crossed.
The other pen I looked at is the Lamy Vista (clear body version of the Safari), but it's yet ANOTHER brand that has its own specialized cartridges. Come ON, people, buy a clue... sooner or later, something's going to go out of stock or become obsolete, and there goes the use of your pen. (Plus, Lamy's pen is significantly more expensive than any of the others I've listed - even with the nice price cut online sellers give.)
(By the way, yes, Lamy pens do have a bottle ink converter that will solve the problem if the cartridges go out of production, but bottle ink isn't as convenient or easy to drag around all over the place as cartridges are. And if you're like me & want to change your colour all the time, you need lots and lots of more expensive bottles...)
*After I wrote this and originally posted it on my tumblr, I discovered they weren't discontinued after all, but the line was revamped. I'll be doing a post about that at some point in the future.