I personally think thats not a problem.
Because we model the application with multiple tables (various Qvds). So, QVW can support your application correctly.
Why? Wall Mart use it. They have terabytes of QVDs. So the success of your project will depends of how You model the application. The solution can be develop multiple .qvw for each area of company. If You dont do, it will load all project in memory (and not everybody will use the full application, wasting RAM memory.