I have been using it for the last eight years, after previously having
used PowerDesigner and ERWin. It is a great product, no doubt.
Embarcadero's delivery & licensing mechanisms, however, are abysmal. Licensing servers, app distribution servers, sluggish Java apps to launch the actual tools and poor documentation of how to configure and use these requiring repeated CS calls.
This is not to mention that there are no slimline versions (read: cheaper) that could be used by smaller companies to do physical/logical modeling for a single platform. I bet this discourages many companies from adopting a design-first approach in favor of only creating data models as after-the-fact documentation on occasion with lesser tools.
Perhaps Embarcadero is not interested in anything smaller than the full enterprise market?