Sorry for lack of detail in first post.
The pen I am looking for is in essence a more durable, refillable version of the uni ball jetstream 101.
I like the pen a lot, as it is also good for maths as well as writing , unlike a fountain pen. However I am annoyed that it is not refillable, and I really just want a pen for life to stop constantly having to buy a new one every 3-4months.
Is it a gel pen?
Yep. I used multiple for school since the third grade (I’m finishing highschool now). While the pen is great, the refils are terrible. They sometimes dry from sitting for ~2 months and become hard and scratchy (most of my multicolor ones are like this). But the Pentel EnerGel refils fit in the g2 (but not vice versa).
Are those refills better than the g2?
Yep. They are smoother from the beginning (which I like for my messy and fast writing) and don’t harden. But they used to be ~3€ in Slovenia while the g2 ones are around 1-2€.
Also, the Pentels don’t last as long from my experience.
Why not use the penter energel pen instead?. I quite like the ink in the g2
Well, I do use them, but the pens don’t hold up as well as the pilots. The coloring disintegrates and some parts fall off. They also feel low quality with the squeaky plastic.
EDIT: the g-2 refils are also slightly cheaper than the Pentel’s.