Volumes 2 and 3 of To Aru Kagaku no Railgun were a joy to read- both when I first read them and when I re-read them. (And hopefully when I re-re-read them. ^^) For a suspense-driven action storyline, that's no small feat.
These two tankoubon cover the meat of the Level Upper story arc. From Kuroko and Mikoto's consultation with Kiyama-sensei (Best. Neuroscientist. Ever.) at the hospital through Kuroko's showdown in an abandoned building with a thug whose abilities have been wildly enhanced via the Level Upper, and the final confrontation with the real "villain" behind the Level Upper scheme, these two volumes aren't lacking at all in the story department. Even after you-know-who gets arrested by Academy City's Anti-Skill police force, there's still Uiharu and Saten's reunion at the hospital (which is every bit as great in the manga as it was in the anime), a brief but very satisfactory follow-up on a few of the other characters who used the Level Upper. (Not including the girl with the crazy eyebrows who
There aren't many deviations between the material covered in the manga up to this point and the anime. The last three chapters of volume 3 take place at an earlier point in the anime's storyline than they do in the manga's, and the manga has one brief scene unique to it that makes Mikoto's "don't give your life away so easily" line to the villain carry more weight. But it's pretty much the same. The characters are all likeable (except for the ones who we're meant to dislike), and they all get their shining moments, ranging from Mikoto, Kuroko, and (yes) Uiharu's bad-assery under pressure (Uiharu is, arguably, the biggest hero of the Level Upper arc) to Saten grappling with what to do after obtaining the Level Upper, to Kiyama just being...Kiyama. (Really specific, I know. lol)
I recently tried another action title containing yuri that I really wanted to like. It had several "hooks" for a series that I should like, but it contained one fatal flaw- sketchy, confusing artwork that made the action scenes look like a blurry mess. Not so in Railgun. The artwork looks nice throughout, but it shines during the action scenes, with Fuyukawa Motoi's clean, dynamic linework and layouts that flow together as smoothly as cream. I also like how the resolutions to the conflicts in Railgun generally rely as much on the characters' reasoning skills as their brawn. (Or powers.) It adds an extra level of appeal that even the most brilliantly executed artwork wouldn't be able to manage on its own.
I would recommend Railgun for anybody who likes action, sci-fi, and/or yuri, but it's also especially recommended for anyone who wants to read a shounen action-style title without some of the draw-backs that the genre is known for, like overly drawn-out storylines. (Yes, I know that Railgun runs in a seinen magazine.) It's (mostly) light fun, without being lightweight.
It would be great to see this series licensed, in both anime and manga format.
Happy Valentine's Day and Happy Lunar New Year! ^^ (My college is holding its annual Lunar New Year celebration next weekend. Definitely looking forward to it.) Here are a couple of Railgun pics in the spirit of Valentine's Day (from these two Pixiv artists):