UPDATE;
I bought both CR & SC now, and want to give feedback to anyone who is interested:
CR: It is great! I have gone through the first 70 CR Official guide Questions and I got only 4 wrong! That is something I hadn't accomplished before. And no, I don't remember the questions from the first time I went through...
It really made a difference. Before I was just guessing on two final options, but now it's like "ok this one is clearly out of scope". Before the CR course I read the powerscore bible (used book;costed only $3; main reason why i bought it), which i found to be not useful at all. Also read the MGMAT CR but that is even worse. I know that magoosh has a similar approach, but don't know, I find e-GMAT more like math than anything else: obey the rules and you won't be disappointed.
SC: I haven't finished yet, but I actually do have deficiencies in more areas than I thought. MGMAT SC looks a bit superficial compared with e-GMAT. I am nonnative, but I had English as a subject in school for 9 years, have no problems at all when watch TV/Movies in english, but gmat is a totally different story. On the other hand, for some e-GMAT might offer a too "rule-based" approach. No, they don't kill you with grammar, but it becomes like sudoku: you have to KNOW that after 1 and 2, a 3 has to follow, and not just to guess or have some intuition.
I find both courses a bit too high priced, but I don't work fulltime and have a certain opinion about "selling" access to already recorded videos.
But to answer my own question:
e-GMAT INDEED offers content above the one in the MGMAT SC book.