Like being in a Rocky movie.
My first impression? Well, it was a bit confused. The game was a bit difficult at first, and only due to the controlling system, which is pretty sensitive. For example, if you wish to crouch your upper body, you'll have to tilt your control stick just a little bit in order to make it crouch instead of moving forward. It's quite frustrating at first, but you'll learn if you have the interest like I did.
Only my fancy for boxing kept me learning the difficult moving system, and it finally paid off when I managed to bob and weave my dancer in a way the opponents missed a lot of their punches. The punching controls are very good, there are own buttons for straight punches and hooks. You know, catch the foe with a few snappy straight lefts and hook him like hell. He'll surely drop after a while. (At least Muhammad Ali did!)
The graphics are very good for a game this old. I really liked what I saw, except the audience are sprites, made of paper. Otherwise I had a really nice feeling throughout the game. The sounds are quite realistic, they aren't any synthetic "POW!" :s, they're splats like you'd hit someone for real. Though, I've never been into fighting in real life, so how could I know? Haha.
I liked the Career -mode, so I played it a lot. It features real boxers through-out the history, so it keeps it interesting. If you're more into arcade, you can always play Slugfest, which has some super punches to knock your foe with a single snap if you time it right. Something for everyone.
As a conclusion, I found this game pretty entertaining. If you're willing to learn the quite hard controlling system, this game suits you fine.The only really bad thing is, that this fun doesn't last very long. The career's finished pretty swiftly, and I doubt that anyone is willing to play Slugfest till the end of days. Anyway, you can find this game for a cheap price, so it doesn't hurt you to try it out!
Float like a butterfly and sting like a bee!