Roku worked well with anything over 6Megs, in my house with up to 4 players going. I have upgraded to 12 megs, and see no quality difference, just able to run more items in the background without any pauses.
I am not using Apple. I have cable internet from Time Warner with a wireless router. My Roku is hooked to that. I have the router in the basement and the Roku is hooked upstairs . I am streaming it on a non- HDTV. It is crystal clear with beautiful sound. I could not ask for better picture quality.