I have a CV643D in an A3000. This card seems ideally suited for an A3000 with its built-in flicker fixer. I use an external monitor switch to lead both outputs to a monitor.
Keep in mind that the Zorro III interface of the CV64/3D has some timing issues when really fast Zorro III busmasters (like the DENEB) are driving the bus.
This can lead to bus errors and broken data transfers.
A workaround is already present in the DENEB, so this is not a real problem, but one thing to keep in mind.
Anyhow, I personally prefer the Picasso IV - while the CV64 (/3D) are nice cards too, but not so flexible as the PIV.
Michael