This is one of those games that often crops up in lists of "most under-appreciated games of all time," or something similar. I certainly agree that this is a terrific game, or else I would not have already played it twice on two different systems. It has a terrific art style, endearing characters, an intriguing story and setting, and simplistic but engaging adventure/stealth gameplay. It even has minigames such as races and a fascinating and addictive photography game, as well as lots of bonus items to find and collect.
However, there is one big problem with this iteration of Beyond Good and Evil that merits attention. This is a PC port of a console game, but for some bizarre reason, it DOES NOT FEATURE GAMEPAD SUPPORT. At all. Your control choice is WASD + Mouse, and for a game with occasionally fixed/changing camera angles, this is not idea. It's not a complete dealbreaker, but if you have the ability to play BGE on an older system (it's on PS2, XBOX, and Gamecube),I would recommend that.
That said, the PC version looks much nicer on today's systems, and runs great. And It's better to play a slightly clunky version of one of the most underrated games ever than not to play it at all.