Starting drawing from manga

Hello there,
I've been learning to draw with a quite simple manga tutorial (here it is, if someone is interested: http://drawdoo.com/topic/anime-manga/), and I managed to improbe my skills in portrait and anatomy drawing, as it turned out.
The question is: is it OK to start learning to draw with manga? I'm quite anxious that my drawing can turn out one-sided a bit, I mean, good skills in outlining the characters, while no attention to landscaped/colouring/etc...