I bought this refill to use with the Uni Jetstream 4&1 after using a Uni
Jetstream 3 with 0.7mm refills (only multi function pen available on the general
market in Australia) and whilst I was exceptionally happy with the 0.7mm
Jetstream I am absolutely in LOVE with the 0.5mm. I bought the pen and refills
because I am a floorcovering salesperson, and as such, I use the pen to draw
house plans. I have tried the 0.38mm but find that they tend to be a bit
scratchy on the plan pads I use (most likely due to the low quality paper they
are made from) whereas the 0.5mm glides nicely over the paper leaving a nice
fine line that doesn't bleed or smudge which is what I was most worried about.
I also use the pen for daily note taking and working out prices for customers on
a variety of different quality paper and it always works flawlessly. i can
highly recommend the Jetstream 0.5mm for anyone who does house plans for the
floor covering / carpet / flooring industry as I have found practically NO
reviews whatsoever for pens for our industry.