I wanted to try a modern multipen with gel ink refills, and narrowed my choices down to the Pentel Sliccies 2-Color and the Pilot Hi-Tec-C Coleto 2-Color. There are MANY other multipens available these days; I wanted to ease into the field by trying out two popular models. I also wanted to start with only two colors because I'm not a fan of thick ass pens, and I assumed that 3, 4, and 5 color pens would be unruly. Besides, my plan is to use these at work, where I typically juggle blue and red pens on a daily basis. I don't really NEED a third, fourth, or fifth color, a mechanical pencil cartridge, a stylus cartridge, etc. A toothbrush or dental floss cartridge might come in handy, but I haven't found one yet.
Both of these pens have been reviewed many times, and I don't really have anything new to add in that regard. Simply put, both of these pens are awesome. They are virtually identical in shape, size, and weight (about 8.6 grams; yes, I weighed them). Both have "normal" sized barrels with ridges near the grip region, both are made of cheap clear plastic, both have pocket clips that enable you to nerd out if so desired, and both are refillable with a wide variety of different colors and tip sizes. Like I said, they are awesome. The primary difference is in their loading and actuation mechanisms. The Coleto refills load from the top of the cap (after opening the lid), and the Sliccies refills load from inside of the barrel (after unscrewing the two halves). The actuation tabs on the Coleto refills are color coded and marked with the tip sizes. In contrast, the actuation tabs are integrated with the Sliccies body and they are neither color coded nor marked in any way. The refills for both pens provide great writing quality, although I do prefer the smoothness of the Coleto refills (they are, after all, based on the killer Hi-Tec-C design). These pens will remain on my desk for a long time.