I’m still new to pointed pens and have just tried this nib for the first time. After practising to get a feel its’ ink flow and capacity (and two blobs from my being impatient), I began writing for a special project and was able to write letters ranging in size from ¼” to 1” in height (or about 18 - 72 pt) with satisfactory line thickness variation for all sizes.
Although it doesn’t hold as much ink as many larger nibs, I was pleasantly surprised at how much I was able to write with it before it ran out.
The Brause 66EF is now a new favourite of mine, especially in cases where I’ll need to write smaller but still be expressive.