I just had a really good outcome with running my Cambridge Audio Azure 851w's (A/B) in a Bi-amp dual mono setting (200/350) and you could go bridged mono blocks (500/800), though I hear the 800w is generous. Best part is you can find them for $700-900 each used and weigh 40lbs each (80lbs still kinda heavy).
Extremely happy with them and I'm not even pushing their power or my wallet!
Happy hunting!