Mixing SSDs and hard drives may not be a feasible option to construct a RAID array.
The only feature that we have validated for using SSDs and hard drives is as cache using Intel® Smart Response technology.
This is similar to what hybrid hard drives like the one you mentioned offer, however you would need to check with your drives manufacturer to see if that type of drive are validated for RAID volumes.
From our side we do not evaluate the performance of the specific RAID configurations used. In this case, if you have concerns about the performance and data transfers on your computer, please refer directly to your hard drive manufacturer.
Having read Seagate and Intel to Demonstrate Solid State Hybrid Drive Capabilities at Intel Developer Forum 2012 (Seagate and Intel to Demonstrate Solid State Hybrid Drive Capabilities at Intel Developer Forum 2012 | Seagate), I thought that buying a Seagate SSHD would maximize compatibility and reduce anomalies. Would have thought the recognition of the Seagate SSHD would be a slam dunk. Despite not recognizing the SSHDs, they are working fine in a RAID1 configuration with Windows 7 loaded on them. Clean install loading the "F6" drivers during the Windows 7 install.