Nessus Scans over a VPN

[Firewall Administrator]

Greetings!

I would like to know whether members of this list have any thoughts about whether one could run successful Nessus scans over a VPN link.  I have read various concerns about running Nessus scans through a firewall, but haven't seen anything about doing it through a VPN. 

What would the potential problems be?  Network latency causing false positives (or false negatives)?  Any thoughts from anyone who has tried this?

Thanks in advance,

TJ