Well this is going to be hard, this manga to me was looking like it had potential to be one of those special ones that would set the benchmark for me when it comes to this type of realistic fighting manga, but recent chapters have really started to make me doubt that, and by recent I mean the last 2 or so volumes (I'm at volume 11 atm), it just seems like the author recycles the same thing every new arc and it is getting a bit boring and frustrating really.
The characters are good for the most part, I like the psychological side of the manga with very realistic personalities and problems for the main characters, it just feels like I can relate to them and they feel authentic, they have substance and aren't just cardboard cutouts like a lot of characters in other manga, the biggest problem however for this manga is exactly in the psychological part and it might just be me, this really might be just my personal opinion and others might not be bothered by it, however to me the main character is just too frail and every time a new "rival" appears he has some sort of identity crisis, it isn't so much that it's not handled well, cause it is, it's built up over several chapters and has some solid reasons every time, it's really not badly written individually but as a whole the problem is that it happens too often and to me it cheapens the main character and makes me resent the manga.
The graphic style is nice, it isn't one of the best looking mangas but it is fairly solid in this regard, I like how the characters look, most of them are unique and generally show their personality really well through their appearance, it is fairly detailed and the author has a good understanding of human anatomy.
The story is fairly generic really, nothing much to see or talk about but it is well written and doesn't really have any major flaws except for the repeating identity crisis the main character seems to have every time some new challenger appears just so he can get beaten to hype said characters and look even more amazing when he eventually beats him.
What I personally really like about this manga is that the author explains a lot of the moves, training and techniques in the fights really well, at times feeling like a training manual :D but at the same time it feels like it belongs there, even though it should feel disjointed and out of place it really doesn't, it adds a good dose of realism to the manga and really I've just never seen this in any other manga I've read until now.
As a closing comment I do want to say that I would still recommend this manga to any fan of more realistic fighting manga, it has a lot of depth, some great characters and is very well written for the most part, it has some flaws that are annoying to me but it really is worth reading.