Yeah, it's pretty darn good. The remote communicates via radio frequency, so you don't need to point the thing at the Boxee. All my friends who come over are pretty impressed by the whole Boxee interface and remote. It's well worth the $200 I paid for it. There's also an iPhone app that lets you use your phone as the remote, and it's kinda cool.
I've looked into XBMC a couple of times in the past, but I just can't find a reason to actually use it. My PS3 serves my Netflix to me very well. I can also stream from my PC to my PS3 if I wanted to, but in reality I just don't have a need to listen to my music in any room other than my office. Sounds like you have a bad-ass setup, and for that I applaud you.
Thanks. I've digitally cataloged my entire movie/tv/music/picture collection and I have multiple tvs in the home. XBMC was the most robust and adaptable platform to serve, sort, and display that collection.