with the arcade, you do get a memory card, but of course as you know, doesn't come with the hardrive. But you will spend just as much money buying the hardrive and all the other accessories that comes with it (elite). A wireless controller, headset, HDMI, Ethernet cable, and a 120 gb of storage (AH) *heavenly music* no.
Something that I don't know is the warranty, if it comes with the Arcade version or not. Either way, get the warranty to whatever one you get.
Between video games...ODST is okay, but probably the nongreatest halo game...except for multiplayer, it's amazing. Forza Motorsport 3...never played it, but I have seen reviews, maybe not so bad. Mass Effect 1 and 2 are said to amazing. That is if you are into RPG shooter style games (similar to Fallout 3 if played).
Really it is your choice. Since the Elite is down to 300 dollars...depends on package (game, whether it comes with two controllers, etc.) I would go with the elite.
