Ok, my impressions on the game at first were a little disappointed and confused. But after a couple hours, I began to love the game. Mind you, I haven't touched other boxing games like Fight Night or even VB1. At first I thought the controls were extremely bad, but after switching L2 to sway control, the game just became a cinch to play. To learn the game, I would just advise you to either play easy or with a friend and experiment with the different punches.
I admit, at first the game was frustrating to pick up. But after playing with my little brother who's only 12 years old, the game began to pick up. With this game, you have to be willing to give it a chance, the learning curve isn't exactly the easiest.
I would agree with thoughts that this game isn't the best. But cowmon, it's onlly $10. However, I think this has been the most "fun" I have had with a boxing game. Fight Night for 360 didn't seem as fun when I tried it out in stores, maybe I didn't give it enough time. But, I would definitely regard this as genuine fun, though it requires some patience in learning the game through trial and error, considering the manual is crap. Why today, I just played through the whole game on Normal, and not once was I bored with it.
Only complaint about this game would be the abusive characters. But it's not that bad if you actually know what you're doing in the game and each characters advantages and disadvantages.
The hit detection and not knowing how much damage is done is not that bad for me. I personally like not having meters and evidence of damage/fatigue. It just makes the game much more spontaneous. Though I'm sure KO's are not random, you have to take into account accuracy/momentum in the shots. In real life, I'm sure no boxer knows exactly which punch will knock him out, much like how this game emulates.
All in all, I would highly recommend this game to anyone, especially with it's $10 price tag.