[meshtheflesh]

Mezzo does what it says it will do. It a very clever programme, but I has had its moments. No lost data, but a couple of us had a period that it was crashing when we tried to restore stuff, updateing our systems resolved this, but it came out of the blue. That aside, we do love it. It is great how you can just drag a session icon across, and it find all the files, and keeps them backed up.
In regards to backing up while doing a session, I do it a bit, but there is the risk of crashing. If you feel you PT system is really solid, then do it, but crashing in the middle of an archive is pretty bad news. It usually will recover, but it is not the best thing. Its can be scary if you have 20gig on one tape.

Cheers
Ramesh