Besides from performance, one could reflect on the following features of SODS:
-As Peter mentioned, authorization, as well as authentication is a part of the software. If your application restriction in data access, you need to perform these tasks at the OS level instead (or in an external RDBMS). Be aware of that you can't put authorization on a column/row level in the OS.
-Built in backup/restore routines allow you do incremental backup. With Base/SPDE tables you need to do full backup.
-Row level locking comes with SPDS. SHARE has it as well, but with significant lower performance, especially during batch load.
-Centralized servers. Means that you can easily close down user access to perform DBA work, backup/restore. Otherwise you may have to do some "kill" on pid's in the OS environment.
Whether it's worth it or not is up to you to find out.
Regards,
Linus
Data never sleeps