Is there something special about the B1/2000s? It is the "added warmth"? I am not opposed to the B1000 but 2x 500w is more than 900w and bridged 1600w is more than 600w.
If I had a dually or any cabinet other than my 810 that could handle a kilowatt I would be more interested in the B2000 I think. Also despite the complicated nature of the BX1600 eq, I actually am quite fond of that style. Also this solves my lack of DI issue as the DI on the 4 pro is hum city.
Simpler amp, warmer tone, mono block.