I put text in the description field for a fact when it makes more sense than using the note field. The description field has the advantage that there is a [Desc] variable in the sentence template language, that you can see the text without having to open anything up, and that the description field can be a column in People View. It seems to me that this latter advantage of the description field is seldom appreciated as much as it should be and it can be hugely beneficial.
The disadvantage is that if you go over 100 characters in the description field, you can lose data on GEDCOM export and drag and drop without realizing you are losing data. But I am finding that for use cases where I can be confident of staying under the 100 character limit, I am switching over exclusively to the use of the description field instead of the note field.
For example, I have a user defined fact for recording GPS coordinates of grave sites, and GPS coordinates will always fit within 100 characters. RM's normal geo-coding facilities do not work for me for this application. To use RM's normal geo-coding facilities for individual grave sites, you have to have a unique place name or place details name for each individual grave site and the coordinates don't print in narrative reports anyway. But the description field works great for this application.