I'm in the market to get an XBOX 360 sometime in the near future, and I'm curious as to what kind I should get. Cost matters most, as long as it doesn't affect system performance. Looks don't really matter to me, either, and I don't think storage will matter too much, either, other than a few savegames. I'm looking to play Mass Effect, Halo 3, Mercenaries 2 (when it comes out), Lost Planet, and a few others. I won't be doing virtually any multiplayer - just not really my thing, I guess. Which Xbox 360 should I be looking at getting - will the core system do the trick? TIA.