Board Thread:Questions and Answers/@comment-187.123.44.47-20140112025249/@comment-5230978-20140112031617

Please don't do it. Read the light novel instead. The manga is badly drawn and mre importantly two fundamental arcs are missing, so it cuts even more than the anime. I recommend you to read all the Index light novels, from the beginning. You can find the novels here http://www.baka-tsuki.org/project/index.php?title=To_Aru_Majutsu_no_Index

I also recommend you to start Railgun manga and novels, if you have not read them yet, after reading the first Index light novel series and the Index side stories, and after Railgun read the New Testament. The best would be to read the novels and Railgun manga following the release dates for a better understanding and enjoyment (aside the SP volume, which I recommend to read after Index SS2 and before the 17th novel).

In Index manga there are only some added scenes (like a flashback of Index, Stiyl and Kanzaki before Index memory loss, how the accidents when Accel was 10 started), so, if you are not interested about them, just avoid, because there are two missing arc and other lacks. Anyway, If you want to read it, I recommend to do it after finishing the rest.