I would search for 804 in speaker forum first.
I own (and love) 805, and to me, and several other A'gon posters, if memory serves me correctly, many people have preferred the 805 to the 804, and if you have that kind of $$, 805 matched with a REL (I think the Strata III is the proper match) subwoofer will get you near pinpoint sourcing that the 804 can't match with the much more spread out drivers, and a MUCH better bass response than the 804. CHeck the stats on teh B&W homepage, teh 4 doesn't go much lower than the 5, and side by side, the 5 sounded more integrated and less artificial.
good luck.
I own (and love) 805, and to me, and several other A'gon posters, if memory serves me correctly, many people have preferred the 805 to the 804, and if you have that kind of $$, 805 matched with a REL (I think the Strata III is the proper match) subwoofer will get you near pinpoint sourcing that the 804 can't match with the much more spread out drivers, and a MUCH better bass response than the 804. CHeck the stats on teh B&W homepage, teh 4 doesn't go much lower than the 5, and side by side, the 5 sounded more integrated and less artificial.
good luck.