yes, as post before: you can mix the disks inside the unit, even in one shelf (may this not work in early SX80 models). But dont mix the disks in one virtual disk (I guess this isn´t possible). It is strongly recommended NEVER mix different disktypes in one logical drive!
For example: set up two different virtual disks (one with SATA the other with SAS) and combine them using an os-related diskmanager to one logical drive.
-> This is not a good idea <- !!!