No bells, no whistles, just works I love that I can use custom grading scales and scoring systems. My elementary school uses EGSN rather than ABCDF. This makes it easy for me to mark scores without having to do grade "conversion" in my head. I would suggest adding the ability to set font style and/or size to make grading scale easier to see at a glance.
Love it! Makes scoring my 6th graders' assignments and translating numeric scores into letters much easier.