Not as bad as they say... But not exactly the next big thing.
Good points:
Sweet soundtrack, cool voice acting, unique level layouts, assortment of weapons, classic sonic gameplay, satisfactory multiplayer, story can be replayed many times without losing appeal. Many different characters from the Sonic Universe, including some from Heroes. Graphics for some levels are quite impressive. Frame rate is quite steady until there is mass destruction.
Bad points:
No first-person shooter mode, AI of enemies is pretty weak, guns fire at any enemy which is difficult to complete specific missions, before-final-stage-bosses are lame. Same sprites, same jump pads, launch pads, crates, blah blah blah.
Glitches:
You do 6 levels before a final boss. In the first level the downtown level you seem to always find 2 chaos emeralds, couldn't they have made 7 levels for 7 emeralds come on. lol. Shadow always looks like he's on ice or something, skates do not recognize floor structure in anyway. Character dialogue does not match the timing for subtitles. lol. what's up with that? it's like shadow says a random sentence about the emeralds and the subtitles say something like Knuckles needs help or something! That isn't really it that's just an example of what it may be.
Bottom Line:
Hardcore SEGA fans will like this game quite a lot and not wear out of it for a long time. If your looking for a good 3D platformer, this isn't a first choice. If you must, try Heroes. It's older and better. 6.7