I have seen a fair amount of discussion re: B&W 6xx and 7xx vs. Axioms, but not much about the 803 and 804. Here's the only thread I found :

http://www.axiomaudio.com/boards/showflat.php?Cat=&Board=HT&Number=119223&page=&view=&sb=&o=&vc=1

I found an interesting thread discussing the aesthetics of the 804s vs. other models, but not much on performance :

http://www.axiomaudio.com/boards/showflat.php?Cat=&Board=Advice&Number=87594&page=&view=&sb=&o=&fpart=6&vc=1

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8