I tried CodeCombat a day after I started working on Army of Robots. I had two big issues of it:
1) The debugger was broken, making it impossible to use in practice (at least for me) - "easily" fixable
2) No focus on learning content
I may port my content to their superior platform one day, but for now I prefer working with a system I fully control so it's easier to incorporate feedback from watching students play.