They are great because they are short but hold such wonderful wisdom.
FF

Your email came at just the right time and I couldn't help but be inspired. It was just what I needed to hear. I know it's another way of God sending His messages
RB

I sometimes wonder if you know how much your daily and weekly Dvars help; inspire; encourage; comfort; strengthen; enable your readers
MS

Often I sign up for newsletters only to find out that I don´t read them, they only add volume to my inbox but add nothing to my life. Yours adds greatly to my life.
ES