Right now we have hundreds of "free demo" trial users on the same db server/database with our paid mission critical users.

I see this as both a security risk and a load issue. I have also seen cases where demo users run large reports and crash the server..

Does it make sense to separate these users into separate databases on SQL? Rather than just have one DB for all users?

My thinking is so one group of users has no effect on the other?

Can one group still pose a risk if we do this? I plan to have them on separate web servers also (windows 2008 r2, iis 7, .net 4.0)