Aha, I have found a MapTool feature without which, I really don't want to switch to Roll20. Mostly I much prefer it, but this is a deal-breaker for me.
In MapTool, when moving a token, it shows the path of the movement through the squares, and furthermore lists the distance moved (with the option of 1.5x diagonal movement, which is used in d20 System games). You could furthermore press a button to create a "waypoint" through which you would path, and it would calculate the total movement with the corner. This is massively easier than trying to remember where you started and counting squares to where you want to go.
Without this, I think I will be starting my campaign in MapTool as planned. I was ready to switch, but this is a non-starter for my group.
I'll be watching Roll20 development to see if this ever gets added, but until then I will be staying with MapTool, despite that programs myriad problems.
