The New Challengers doesn't really add anything to what Turbo already has. Sound effects are like scratching chalkboard
One positive aspect about the game is that it is Street Fighter II. You have the classic playable characters like Ryu, Ken, Chun-Li, Guile, M. Bison and so on. You also now have the "New Challengers" like T.Hawk, Fei Long, Cammy, and Dee Jay. While the names themselves are now ingrained in the SF lore, I wish I can say the same about their gameplay. T. Hawk is a bit slow and some of his moves are difficult to master. Fei Long does his Bruce Lee impression, but he's no Bruce Lee, and definitely not Ken or Ryu. Cammy is no Chun-Li. And Dee Jay? I don't know.
The biggest drawback to this game is the sound. The character and announcer audios sound very muffled, which gives us a clue that the SNES's hardware power has been pushed to the limit. Other drawbacks are no sound test, no ten-star Turbo code, and of course, no online play.
If you want to invite your friends and play a tournament mode, this game does feature a sudden-death bracket mode to determine who's the best Street Fighter in your neighborhood.
There are some subtle differences with the character moves such as Ken's fire-fisted Shoryuken uppercut, Ryu's red-flame Hadoken fireball, their modified cyclone kicks, etc. Yet none of these moves improve gameplay or give you any reason to purchase this game.
If you're a die-hard SFII fan and a collector, then this might be for you. Otherwise, Turbo is the best edition out there. If you're a 360 or PS3 owner, wait for the HD version to come out online.
Overall: skip this one.