No RROD on xbox slim, but it's still susceptible to failure just like any other consumer electronics of course. But it's pretty reliable (playing it for 12 hours everyday and still no problem).

Last time the problems of RROD are speculated by the design issue (microsoft skipping vlsi vendor for the graphics at some phase) or by the type of solder being used, of which both are already remedied in the current production. so no worries.

there's no xbmc for xbox360, but it comes out-of-box with media player and connectivity to media files on a computer.