Re: high level inputs vs low level-- I would check some hifi blogs about this. On whatsbestforum.com, the suggestion is that low level might be the better way to go. Personally I have not tried this out, but Kal Rubinson, who is a senior editor at Stereophile, says that low level inputs are better to use.
And again, personally I am no longer interested in spending >$2K on a sub that might die in a decade, like my last sub. That's why I'm suggesting the HT-1205 @$699.