The inherent problem with creating a basketball manga, is that Slam Dunk! already exists.
Fujimaki is competing directly with Inoue Takehiko, which is generally unadvisable. So it's almost impossible not to draw parallels with what Slam Dunk was; a manga that had deeper and better paced character development across the board, more realistic rivalries and characters you could root for harder, better humour and less nonsense shouneny titles like the Generation of Miracles, the King of the North/East/South/yadda yadda and the Uncrowned Kings.
It's also somewhat in the shadow of Eyeshield 21 in that that manga took a very shounen stupid name and 'unrealistic capabilities of highschool students' approach to american footbal, a little like Kuroko no Basket did to basketball, but did it 'properly' in a sense, and went for the whole hog with a different theme for every different team and crazy moves and move names to suit that theme.
Slam Dunk! is a very realistic approach to a sports manga while Eyeshield 21 is anything but that. Both those mangas excelled at what they tried to achieve, I suppose my problem with Kuroko no Basket is that it kinda straddles the line between the two and doesn't manage to do either as well as it could have.
Not even gonna think about comparing it to Real, that wouldn't be fair.
As its own free-standing manga, it's good. Maybe slightly above average, but good. It stands out in its theme of Kuroko wanting to play basketball that's "fun" and actually enjoying the game, and influencing others, including his old teammates, to do the same. Certainly has its share of comedy moments and a very likeable cast. Having the main character be a supporting player on the court rather than the ace is a nice twist away from normal sports manga conventions but otherwise it's a nice, kinda-just-above-average sports manga that doesn't do much that hasn't been done better elsewhere. I'd recommend other sports manga before this, but hey, it's not Prince of Tennis, which can only be a good thing.
EDIT: Although, it does get rather dull later. Most sports manga have a tendency of following the "Team faces seemingly insurmountable circumstances, team falls behind in points, team/player(s) overcomes some ineptitude, team beats opposition by >10 points, rinse and repeat with a stronger rival each time until team gets beaten, train, train, train, and repeat until team beats biggest rival/wins toughest tournament." formula (gratz to That3rdGuy whose summary was accurate and concise enough for me to nick it 😛 ) - other sports manga often survive on making this pretty damn repetitive cycle feel a lot less repetitive than it is. Eyeshield 21 does so mostly by having Hiruma Youichi exist, for example, and also by having radically different teams for each game. One game they're fighting an Egyptian Pharohs-themed highschool American Football team, the next they might be fighting elite buddhist monks and the next they might be fighting dinosaurs. Baby Steps also does something similar (though not nearly as radical) with every game posing a new challenge to the main character (when he doesn't win easily at least) - psychological issues like mounting anger, pressure from crowd, as well as physical issues like fatigue. Slam Dunk! circumvents the problem by being jaw-droppingly great, mostly.
Most of Kuroko no Basket's efforts to deal with this... design flaw in the sports genre is either half-assed, unsufficient or both. Games feel like they just drag on in the later parts, as well as new rivalries/characters that feel quite shoehorned.