... to know the progress, I rely on 'get snapshot for tablespaces' and sometimes 'direct reads' in the database snapshot ...
They may not show you the completed percentage, but atleast you know, your restore is working and where you stand ...
If you are using vendor storage systems (like TSM), you can use their facility to view the progress ...
For eg, if you use tsm , dsmadmc command followed by 'q sess' will help to know how much data is read from the storage system
HTH
sAthyaram