Compatible?

I have been doing some research on SQL Server 2005 Express. We have recently purchased Visual Studio 2005 Professional Edition which comes with a copy of SQL Server 2005 Developer Edition. My question is this: Once we complete development using VS Pro + SQL Server DE, will we be able to load SQL Server Express on the client's machines and be able to have full functionality of the database that we have created to be used with the program? I have read that SQL Server Express IS in fact compatible and fully integrated with VS Express, but i have not read any information saying wheather or not it is integrated with VS Pro/SQL Server DE. Does anyone know if it is or not, and either way know the difficulty in converting it (ie. loss of data, tables, etc)?

Short answer: Yes, they are compatible.

Long answer: SQL Express has a smaller feature set than SQL Dev. If you've used functionality in your application that is not included in SQL Express, then it will fail on SQL Express. As far as the database though, the files are exactly the same and can be transfered from one Edition to another.

You can check out the SQL Server Feature Comparison to determine if you're using any features that are not available in SQL Express.