Hey Mark
Using SharePoint Form Libraries or SQL server directly really depends on
what you want to do with the captured data latter on down the track.
e.g. if you are planning to have another automated system pickup specific
data from the logged call center requests or even a future look to report on
call center statistics then a SQL server would probably make this easier.
However if the requests are purely user driven and based on a set workflow
then you sharePoint option is ideal.

Your primary driver in this should be what you are trying to achieve in this
Pilot. Once you have that locked down then you can make a firm descision on
the appropriate storage technology.