After reading Steve's post called Pens and Pen Loops, I decided that it was time for me to have a look at my pens and write about the subject too.
When I purchased my first Filofax back in 2009, I just used any old pen that was laying around, but over time I've become a bit more picky and have decided to treat myself to something that I really enjoy using.
Here are my favourite pens to use with my organiser (including two recently acquired vintage ones on the right):
Ballpoint - Parker Jotter
I don't remember a time when there wasn't a Parker Jotter knocking around in the house when I was a kid, but I hadn't used one for quite some time until I started getting into vintage Filofaxes with their teeny-tiny pen loops. I think I'd been using a freebie biro in my first Winchester which kept drying out, so I searched around and found my faithful burgundy Jotter. From a pen loop point of view, I don't think that you can go wrong with a Jotter as they're slim enough for most organisers.
Gel pens - Pilot G2 Limited
I love a G2, so I decided to upgrade and buy a gold Limited version, which has a nicer grip. However, rubber pen grips are not a Filofax's best friend, so this is a pen that will either just have the clip attached to the pen loop or I'll use an Oli Clip to keep it inside the rings.
For highlighting and for a bit of colour - Staedtler Triplus Fineliner
Before I started using gel or fountain pens more in my organiser, I'd use a normal highlighter, but moved over to Triplus fineliners as otherwise there would just be smeared ink. Instead of highlighting, I will just add an asterisk or shade around something to make it stand out. I also like using a different colour when using my Hobonichi stencil to draw lines or checkboxes.
Most of my organisers haven't had two pen loops (apart from the Dundee and Van der Spek), so my small Oli clip is attached to the flyleaf and the second pen sits within the rings.
Fountain pens - Kaweco Sport, TWSBI Eco and vintage Parker 51
For a long time, my favourite fountain pens to use with my organiser were my Kaweco Sport and TWSBI Eco. I've found that the Kaweco is small enough for many pen loops, but it also works with a Muji metal pen loop like this with a Kensington:
My TWSBI Eco is too large for most of my organiser pen loops, but it'll happily sit within the rings and is large enough that it doesn't tend to fall out, so I don't need to use an Oli clip.
I also have a couple of other vintage pens (the two that are placed vertically in the photo above) that I'd promised to get working for a family member, so I may be able to keep one of those and instead donate some of my others instead. The black vintage pen is a Parker Slimfold, but I'm not 100% sure about the blue one yet, as it doesn't have a model name on it, but it might be a Parker 17 Lady.
In general, I think that the best organiser pen loop that I've come across is on organisers made by Cordwain Higgler (sadly no longer trading) as they are adjustable. The leather has a slot cut out of it and then it feeds through itself to loop round to allow a pen to be inserted.
What are your current favourite pens for using with your organisers and do they fit in the pen loops?