Further shows shelly has all the cool toys I've been looking for a black 0.3mm for the longest time for a sane price but they are all nuts.
I went through the same lead breaking phase with the 0.3mm but if you stick with it you will reduce the amount of pressure you put on the tip leading to less breakage. Also leads to a waaaaaay nicer writing experience. I used to get bad pain while writing because I used to hold pencils so hard. The 0.7 mm pencils seem like crayons now. Also depends on what lead you use. Softer will break faster but will also lead you to hold the pencil with a softer grip a lot quicker.