IMHO the finest details using the single screen pixels instead of larger squares that cover bunch of clusters at once is more precise and for me thus giving more confidence. Also the detailed zoom and information about the file under the cursor are significant improvements, if you are interested in what's going under the hood.
Regarding the colors, they are explained here and could be changed in the scripts or using the GUI mentioned above.
Regarding the colors, they are explained here and could be changed in the scripts or using the GUI mentioned above.




Other defraggers like those from Auslogics and IObit certainly look better with their more conventional interfaces--no contest there. But I think developer Jereon Kessels is on to something with JkDefrag and now MyDefrag. Considering it's free, I definitely consider it worthwhile software; I just wish the logfile was more complete like JkDefrag.