would b&w 802n be an upgrade to my b&w 804S?

Honestly you are not going to get much difference other than an additional bass aspect, and if your sub is crossed over correctly this is a moot point. Plus if you do not have a separate amp to drive the 802's your benefit will be minimal at best. I would keep what you have if you are happy so far IMHO.

Baranowski, your anthem amp will easily drive the 802n. It's a beast of an amp and made to drive a good full range speaker. Personally I'm not a fan of the metal tweeter used but if you want to stick with B&W the 802n is your next step up. I would look for a good price in the used market for the 805d and then go with good subs. The 805d is more extended and much smoother than the 802n and the mids seemed less dry.

Rose...anything can drive the 802's for sure...but to get the best of what they desire its best to have them on monoblocks or to their own amp. The Anthem P5 is suitable but if he is running the other 804's off of this amp he can make breakfast with it in 10 minutes...I like my eggs over easy with crispy bacon please.

Plus the 802Ns are not much more different in sonic range than the 804S. Plus we are talking about home theater and not a 2 channel or musical application as the OP states. His benefit to go up to the 802N will be minimal at best in his home theater set up.

If the sound will be improved minimal at best, then i will pass on the speakers.

thanks

If you can't tell the difference or like what you have, than keep what you have. The N802 is a substantial upgrade from an N804. There are audible reasons it is two models up and way more money than the 804.