Sent a trust message, not sure if you received it as never used that forum function.
Given the choice I'd always go for 4x 65's over 2x 80's
The extra 5Hz bass extension of the 80 isn't going to make much difference to the sound. We do most of our listening at low volumes, so the sound spread from 4 speakers works better for that.
When you want to crank up the volume, the surface area of 4x 6.5" drivers gives you 33% more driver area than 2x 8", and since bass and volume often come down to how much air you can move, then more driver area means more air moved.