The Self Service portal provides a modern UI for the logging of requests and calls through the service catalog. This modern UI experience is very well received by our customers and allows for end users to not have to be concerned with whether they are logging a request (with a workflow associated with it) or a call (IPK).
One thing that confuses customers is the multiple reference numbers received when using the Service Catalog i.e. the Service order number and the individual references for the calls or requests raised as part of that order.
It would be beneficial if a system option was included to be able to hide the service order number from being visible after the catalog item has been submitted.