We have a customer running a mix of C series and SX units and they would the touch screen to be the same across all units. Is this possible through software upgrading? Or will they have to swap out the C series for SX
The C series will only work with the Touch 8, and newer SX's (10 and 80) are Touch 10 only. The SX20 can be used with either. So you won't have the same panel with C's and newer SX's, but if they are running the same TC software the GUI on the touch panel should be about the same aside for the physical differences. On newer SX's though you might want to run CE code rather than TC, that's going to be the code base going forward.
Note that you will lose features if you downgrade the SX units from CE to TC software.
Check these release notes: http://www.cisco.com/c/dam/en/us/td/docs/telepresence/endpoint/software/ce8/release-notes/ce-software-release-notes-ce8.pdf