I prefer it over the well-known Staedtler sharpener for two reasons: firstly, it has a bunch of extra attachments that allow you to sharpen any 2mm lead holder and not just the very thin ones. Secondly, the guides provide stronger tips that don't easily break. The equivalent sharpener from Stadtler seems to be of higher quality in terms of feel and appearance. However, it doesn't offer these two very important features that I mentioned, so I keep it as a backup and use this one instead!

PS A drop of oil inside the axis, and a little on the blades, will do it good and keep it working for a very long time. I had my first one from school when I was studying Technical Drawing and I lost it in my 30s, while it was still working!

PS The best sharpeners for 2mm are these barrel ones, like the KUM Automatic Longpoint, which sharpens everything and has both 3.15mm and 2 stages, for wooden pencils plus extra blades!!! Also, the small but miraculous ones, which are only for 2mm and usually cost 25 to 30 cents, from M+R and Faber Castell. The top-notch KUM also produces one, but I prefer the ones I mentioned. Finally, Faber Castell has another great sharpener, but I mention it last because it doesn't have the value for money that the ones I mentioned have, the 18 66 00. Although it is of top quality, it is only for 2mm and 3mm, and it doesn't come with extra blades as a gift. So the KUM Automatic Longpoint, which costs the same, is by far the better choice.