This game is great fun, if you have the money to spare or if you see it in a bargain bin in the future then buy it.
For starters you still have the original story of the original game, this is of course good. You still have a similar level of graphical detail that you could find on the Dreamcast version, another thing that is good. The core game-play of Rayman 2 is still there and that is one of the best parts, when I play this game it doesn't feel like a port to me at all, it almost feels like someone made this game specifically for the 3DS, now I know this isn't strictly true but it is just the way this game makes me feel and I like that.
Another good thing about this game, it is still possible to obtain 100% completion, now I haven't had this problem but I know it can be possible when porting a platformer game, some items may not be obtainable due to lack of port quality and lack of development time, so this is something that can put your mind at ease regarding it being a completable port because I don't know about you but I would feel seriously ripped off and saddened if I put 20 or 30 or even possibly 60 hours into a game just to find out you can't reach the end or get a high score, plus on top of this they have your money to boot which you put even more time into earning.
Even though there are the positives about the game there are negatives, and these can make the game worth less than it's price tag. For starters the frame rate isn't perfect when you have the 3D turned on, but it is still optimal enough for smooth gameplay and animations to a certain extent. Secondly the 3D wasn't developed properly into the game, you will find yourself seeing double sometimes, not by a lot but it requires more effort to stay in the so called "sweet spot" of the screen in order to maintain normal vision. Adding onto this the cut scenes are a bad example of the 3D, with the 3D at any setting you will see double vision, I don't know how this happens but they obviously didn't take the time of day to port the cut scenes into the Nintendo 3DS's 3D capabilities properly.
Thirdly the sound is over amplified through the speakers this isn't a big flaw but it can make the experience feel less seamless even though it is rare and for a limited period of time. Fourthly the game music doesn't always play when it is supposed to like queued in the Dreamcast version (I saw this in online videos). Lastly there are 1000 lums in the game world, *SPOILER* Razorbeard eats one so this drops down to 999 and you still get 100% completion statistic for 999 lums, but you can find the 1000th secret lum in the hidden area like you would in other games, now to reach this lum you have to bounce on a spider web to reach it like in the original version, in this port the spider web doesn't bounce making it virtually impossible to get it. But don't worry you can still get it by jumping and gliding from the top of a barrel behind the spider web, you then must land on top of a spider crawling just below the skulls left eye and bounce off it to reach the lum.
Now as for the actual game it features a decent cast of characters that you will meet and interact with along your adventure. The levels are designed incredibly well, they are imaginative, beautiful, and satisfy your needs for seeing another world. The story isn't bad but it serves the progress of the game well mechanically. The cut scenes keep the game together and aren't redundant when you watch them. The music is good, although I have read the N64 version had a better variety of game music.
Overall this game is great fun and if you have the money to spare or if you see this game in a bargain bin in the future then I strongly recommend you buy it, but if you are reading this around the time of the 3DS launch and Rayman 3D isn't your strongest choice of the launch line up then go for something else that you are certain you will enjoy. Although there are these problems I have mentioned if you want the best experience of the original game just buy a PS1, PC, or Dreamcast copy of the game and play that, plus it is also far cheaper (I do not recommend the N64 version because I read it has poor controls and some parts in the game require precision to succeed) and you won't see the problems I have mentioned happen in the 3DS version as these are 3DS version specific issues. I will give this game a score of 7.5 out of 10.
Thanks for reading my review, have a nice day. :)