Unless you really want to use OS4.1 Classic I would suggest a Blizzard PPC & GREX, this is the fastest PCI option for A1200.
As has been said you can't use the Micronik with a Mediator, they both use the A1200 passthough. I understand the Micronik works better with A4000 accelerators, if you were going to get a CSPPC then I would suggest the Elbox Mirage Pro Tower and mediator 4000D, I've had this setup and it rox :banana:
Right now I just use mine with a CSMkIII since my CSPPC died but I still have my BPPC's.
I ran a Blizzard 1260 with a Meditor 1200SX for a while, it's a very nice setup, I would always go for that instead of the Z3i
You might be interested to read my A1200T project thread:
http://www.amibay.com/showthread.php?t=5643(I think I saw you also on Amibay)
I have a few threads over there so if you need any tips let me know!