More a brawler than a boxing sim, this is no Fight Night, but given the woeful lack of PC boxing games, I'll take it. My only real fault with the game is it's clunky as crap sometimes. You can dodge an incoming punch, but the movement is sometimes too clunky for you to move in and counter in time. Fight Night (my favourite boxing game franchise, so naturally my go-to comparison, I make no apologies) offered very fluid controls, this feels much heavier and .. well just heavy, and I felt like I was moving on a grid (like the original tomb raider, you know what I mean), it really broke immersion and I never felt I was fully in control of my guy.
That said, very satisfying to KO folk. It's interesting though, the fewer rounds you set it to play as, the more damage you'll do. My first match I set to 15 rounds, and I ended up going the distance without getting the opponent's health bar down halfway. Set it to three hours, however, and you'll get two KOs per round easily. For the best balance of realism and arcade brawler I guess go with ten rounds.
Minigames to level up your boxer are repetitive but more difficulty is added to these too as you go through the escalating boxing tournaments, which was a pleasant surprise that caught me off-guard. Sadly, these involve not just the buttons but the analogue sticks, and I often screwed up because I find it difficult to judge an angle to aim the stick at, so when it wanted the right stick to go up to the right at 45 degrees, I often missed it by going too far 90 degrees, or vice versa, which was frustrating and felt like a cheap fail.
In lieu of more polished boxing sim alternatives this will serve well enough, but it could use a bit of polish. More variety in unlocks wouldn't go amiss either, the gear and especially the hair and stuff is far too limited, and you stand a good chance of fighting a clone of yourself, which is amusing but kinda weird :P