Audya5 has a "normal" 2.5" HD with standard 44-pin IDE-connection.
So theoretically you could use a SSD.
BUT : SSDs only "live a long time" when the operating-system supports them. Otherwise the memory-cells will be destroyed very quick. ( within months, depending on the number of WRITE-Accesses ).
In PCs youŽll find this support only in Windows7 and some of the latest Linux-versions ( maybe Apple / MAC as well... )
But Audya has obviously an "old operating system" that does not support SSD-features.
The german support told me in april 2011 that Ketron is still working on this problem. At that time they DID NOT RECOMMEND the use of SSDs in the Audya.
But 4 months ( since april ) is a long time, so you could give it a try.
Of course you should be able to do a "sector-copy" ( like with "Acronis True Image" ) of the original Audya-HD. "Normal" copy ( e.g. via Explorer ) WILL NOT WORK !
This kind of copy-process will NOT ! work properly via "Audya to PC" USB-Connection ( it also would last more than 10 hours ). You have to extract the HD from the Audya and connect it directly to the PC ( e.g. via an external 2.5 HD case ). With that constellation it took me only 20 Minutes to complete my sector-copy.