With the latest update of DT4, markdown looks great, to me anyway, in both “source” and “preview.”.
Many moons ago I updated DT and it made markdown rather ugly. However, since I use DT as my main writing app, I simply overlooked the change and continued on.
I’ve tried several Markdown apps to actually write in, but in the end, having my data in DT, and writing in DT, just made the most sense.
Hope having a positive post is ok. 