I'm trying to decide which is the best ER diagram software to use and would appreciate any feedback or comparison on the following solutions (or other recommendations)-

Case 2 ($329) http://www.casestudio.com/enu/default.aspx

Datanamic Dezign for Databases 3 ($229) http://www.datanamic.com/

I'm going to use an admin solution like EMS http://ems-hitech.com/mymanager/ to manage the database and users because I can't find any ONE solution that does both database user management and ER diagraming (if you know of one, please let me know).

I have also thought about drawing solutions like Visio and SmartDraw because if I'm going to use EMS I may get into problems using two solutions that both have the abilty to alter table structures (e.g Case 2 and EMS or Datanamic and EMS). If I stuck to EMS for the table structures, relationships, etc and a drawing solution (that can't alter table structures) then I know I am safe. I guess the only thing I would miss out on is reverse engineering (which would be useful).

Any advise on the best way to go would be most welcomed.
Thank you.