Ad:
If someone from Cisco knows how the device reacts to the disk change s/he can help us to accurately answer your question about the impact of changing the size of the desk.
What is the provisioning policy for your virtual disk? is it "Thin Provision"? If yes, the 80 GB may indicate the current data on the disk becaue the "Think Provision" disks consumes as storage as it needs and does not eagerly reserve the whole desk space on the creation time.
If the 80 GB is fixed however and you want to extend the HD storage I suggest that you take a backup, re-image and then restore the backup again. this will save you any side effects that my result due HD size change.
HTH
Amjad
Rating useful replies is more useful than saying "Thank you"
Rating useful replies is more useful than saying "Thank you"