When building your test environment, always start from scratch. Document how
you build the system ACCURATELY and EXACTLY - you will need this later.

Create a few user accounts, and then use MailStorm.EXE (the actual name may
be slightly different) to send some mail messages. This can be used to
quickly populate a database and bring it up to a reasonable size (say 1
GByte or so). (Remember as 1 message to 1000 people generates the same
amount of database space as 1 message to 1 person you actually need to send
1000 messages).

Then do some ADSM tests - backups via GUI, backups via command line, backups
via schedules, restores both with and without log files.
Then kill the server (format c:) and re-build it, and restore the data.
Then get a second server (i.e. different hardware) and build Exchange onto
it and restore the data.
Then use MailStorm again to increase the database size to 10 GBytes or so,
and re-check the performance.

Cheers, Chris