Yes you can use an SSD with the CSPPC, but the UWSCSI will max out around 36 MB/s. For that the type doesn't matter unless you feel autotrim is needed (not IMHO).
Termination with an UWSCSI should always be "Active and Wide" at both ends of the cable. Unless you are running OS4.1, I would use the slow devices on the slow buses, i.e., the SCSI2 CDROM on the SCSI 4091 for quicker throughput. Keeping devices on different buses allows copying to occur without bus slow downs and reversals.
