I have 64bit server for hybrid Core and one 32bit MD. They are working fine.
In my experience which is not so wide I can suggest do not use S3 Video Adapters Trio 64+. I tried it and MD didn't display anything after boot.
Also, MD should support PXE to boot from tftp. I have DVB card SkyStar1 but I didn't configure it to work under Pluto. Also, I'm waiting for MiniMac to test it as MD.