How many clients you have? Embedded will handle up to 5,000 clients. If you have more than SQL is the way to go.
http://www.symantec.com/docs/TECH102547
https://www-secure.symantec.com/connect/forums/embedded-database-or-sql-database
https://www-secure.symantec.com/connect/forums/embedded-database-vs-sequel-server