My main issue is the number of available channels for 5-6 HD's and 4 burners. I'm running 3-4 SATA HD's and 2 PATA HD's. (2 RAID arrays) The PATA can of course be run on SATA, but still need ports to do it. So If I'm going to have to use a PCI controller anyway, then there's no point in looking for 4 SATA ports on the board. The Soltek has everything I need due to the extra IDE port. The MSI does not.
So If I resign myself to using a PCI card, the next issue will be getting the board to boot with an extra RAID controller running. Part of the reason for the upgrade is to put my main RAID array on the chipset and boot from that, but many boards will not boot with a PCI RAID running. My NF2 will only boot if the MB SATA is set to base mode or disabled.
Another option would be a non-RAID SATA card to give me the extra ports I need and run both arrays on the chipset on NF3. That option might also give me the best bandwidth situation with less stuff on the PCI bus.