I’ve used my 3 micron diamond stones on a number of knives so I consider them at least somewhat broken in. In spite of that, they feel rough and seem to produce deeper and less consistent scratches than the 1000 grit stones. Have other users experienced this? Where are you using them in your sharpening progression?
The 3 micron stones may be coarser than their name indicates. I've never investigated their actual grit rating and I hardly use them since I'm very happy with the other diamond stones, the ceramic stones and the diamond film.
If these are the ones that are based on DMT’s EEF (or is it XXF) stone… they take a loooong time to break in.
Great for deburing an edge though. 
They are made by DMT IIRC.