It was towards the end of summer and I had yet to ever read a manga and I had tons of time on my hands so I decided to read the manga adaptation of Neon Genesis Evangelion, as the anime before had left in a sort of confused state and I didn't totally understand what people meant when they said that Eva is deep, but that was before I read this...

Impression:
From the very get go I was pulled into the story just as episode one of the anime had done before, but this didn't feel like the Eva I previously knew, it was different as some of the events in the story were different in comparison to the anime, getting from point A to point B was a new experience though the manga does not stray to far from the story laid out by the anime however the first 3 volumes of the manga were already out before the anime had ever aired.
The best way to put it is that the manga is like a different interpretation of the same story done by the anime, the story and the characters are handled a little differently, as most of the manga was written after the anime's alleged end so the writer already had a good idea of where to go so everything seems more planned out and every event has purpose and a feeling of progression.
Now I can't say what the fans of the original series will think of this manga in whether they will like it or not but as a bit of advisory the story (as I said before) is handled differently, thats all I can say for that.
If you are a person like me who watched the anime and was not totally satisfied with it and felt like they kinda gave up and half assed it a little bit, or if you down right hated the anime for the typical reasons a lot of people hate Eva. (not gonna get into that)
Then good news, this won't make you depressed, but it's not like a generic mech anime it's still eva and the manga still keeps it's eva charm were not everything is perfect and it still keeps it's dark psycho-analysis and religious symbolic undertone and it doesn't sacrifice it's complex story either and all of the elements of eva are still present, but instead of bashing your head on the keyboard at the end of the series, you'll actually get it, or at least I got it, I can't really speak for everyone but that was pretty much my experience.
As for anyone who is arriving fresh with no prior knowledge nor experience to the franchise then you should expect to be taken for a ride.

Characters:
The characters in the manga are very well expanded on for the most part as eva is a more character driven story but even so just to get this out of the way one major con with this (and this applies to your particular taste) was probably Asuka, I didn't find anything wrong with her character in the manga but at some point of the story she was a little shoved off to the side and became more of a secondary character that only developed to a certain point though this also happens in the anime I think it is more noticeable in the manga, I don't particularly care for her character but there are other people who do so I'm just including that for their sake.
As for Shinji our lead male protagonist, he's actually not half bad in the manga, he's still angsty teenager we get to see more of his thoughts and he becomes a more understandable character where you see things from more of his prospective though at times I think he was a little more courageous in the manga I felt like I understood more on why he would do the things he did that in the anime made me completely hate his character at times, and I found that I liked him more in the manga with out it feeling like the shinji from the original series was completely replaced.
Rei was an interesting character in the manga as she seemed a little more talkative than what she was in the anime but there was also a lot more of a focus on her character in the manga, her character development happens pretty smoothly and the turns out to be a very interesting character as the manga goes more in depth with her.
Ryoji Kaji, who isn't even a major character in the story was also a very interesting character as the manga goes into his backstory which does a great job at explaining his motives for his actions in both the anime and the manga and it gives his character a whole lot of depth.
Another character who gets a lot of development was Kaworu who comes in the latter half of the story starts out seeming kinda creepy and cold but eventually begins to develop more of a personality.
most of the other characters are relatively the same as they were in the anime but the manga seems to take more time going in depth with them.

Final verdict:
I'm going to have to give this one a 10 out of 10 which I don't normally do but I can't find to many flaws with this manga, now like I said before some of the more hardcore fans of the anime might say something different but for anyone that is a little confused with eva, I highly suggest reading this manga.