[Blade Raider]

Here's a list of the original's codes.

0000 - VS mode. Insert two keys in a row from one of the same versus movie to get a special VS sound.
0001-0035 - Team Names
0101 - "Akemashite Omedetou" [Happy New Year]
0120 - random beeping
0223 - "Minna! Konnichiwa!" [Good Afternoon everyone]
0414 - Special Mode plays back every sentai team name
0508 - "Okaasan, Otousan, Itsumo Arigatou!" [Mother, Father. Thank you always] can also be activated by entering 0619
0730 - "Super Hero Time! Gokaiger! Hajimaru zo!" [Super Hero Time! Gokaiger! Begins!]
0833 - "Minna! Oyasumi!" [Good Night, Everyone]
0840 - "Minna! Ohaiyou!" [Good Morning, Everyone]
1111 - "Kaizoku Sentai Gokaiger"
1224 - "Merry Christmas"
1992 - "Gattai! Daizyujin! Tatakae!" [Combine! Daizyujin! Fight!]
2001 - "Gattai! GaoKing! Hasshin!" [Combine! Gaoking! Launch!]
2002 - "Gattai! Senpuujin! Ganbare!" [Combine! Senpuujin! Good Luck!]
2003 - "Gattai! Abarenoh! Gabare!" [Combine! Abarenoh! Good luck!]
2004 - "Gattai! Dekaranger Robo! Ikuze!" [Combine! Dekaranger Robo! Lets Go!]
2005 - "Gattai! Magiking! Ganbare!" [Combine! Magiking! Good Luck!]
2008 - "Gattai! Engineoh! Tatakae!" [Combine! Engineoh! Fight!]
2009 - "Gattai! Shinkenoh! Hasshin!" [Combine! Shinkenoh! Launch!]
2010 - "Gattai! Gosei Great! Ikuze!" [Combine! Gosei Great! Lets go!]
2011 - "Gattai! Gokaioh! Tatakae!" [Combine! Gokaioh! Fight!]
2222 - "Ikuze! Gokaioh!" [Lets go! Gokaioh!]
3333 - "GokaiMachine! Gokai Ni-Hasshin!" [GokaiMachine! Heroic Launch!]
4444 - "RangeR Key wo ippai Irete Mawasou!"
5091 - "Hasshin! GokaiMachine!" [Launch! GokaiMachine!]
5501 - "Hasshin! GokaiGalleon!" [Launch! GokaiGalleon]
5555 - "Tatakae! Gokaioh!" [Fight! Gokaioh!]
6666 - "Atarashi Senshi no toujouda! Minna! Ouen Yoroshiku!" [Everyone! A new warrior has arrived! Nice to meet you!]
7777 - "Super Sentai Series! Minna! Ouen Yoroshiku!" [Super Sentai Series! Everyone! Nice to meet you!]
8888 - "Kaizoku Sentai Gokaiger! Ouen Yoroshiku!" [Pirate Sentai Gokaiger! Nice to meet you!]
9999 - "Tatakae! Gokaiger!" [Fight Gokaiger!]
9130 - "Data Cardass! Super Sentai Battle Dice-O!"

The Legends codes can be found here (not sure if complete). Scroll down to see the physical differences:
http://www.tokunation.com/showthread.php?p=15982

Biggest difference (sound wise) is the Legend having Go-Busters and the 0000 codes doing completely different things. Aside from that, Legend does have less codes overall and focuses on holidays. On the great side of this, the team codes (0001-0035 or 6) and Special Mode code (0414) work on both. This means you don't need a single key to hear all the team names.

Honestly, get the one you like more or the one that meets your budget. I would not recommend the Korean one though. You won't regret buying it.