The feature that all streamers have in common is that they use magnetic media, which means that streamer tapes are sensitive to electric magnetic fields, cellular phones and other environmental factors, such as sunlight and humidity. That's why data safety is highly dependant on the way you handle the tapes. Be careful to store tapes in a dark, dry and cool environment. Also, keep both the drive and the media taped well protected from dust.
I'm sure that many people consider streamers as old-fashined hardware. However, there is one very important type of backup which makes a tape drive much more valuable than other solutions.
First we should make clear that it is no problem to backup single files, as those can be restored easily. In contrast, it is not that easy to re-install a fully-featured and of course working (!) Windows NT or 2000 Server that may be running sophisticated configurations of server software like e.g. Microsoft Exchange server (a software which will give you a headache until it works properly). In addition to the basic software setup - although 'basic' may be the wrong word for the installation of a server - a disaster recovery backup will include all user data (email and system accounts), the latest version of server-based network applications like replication utilities and other administration tools.
Disaster Recovery is a feature that is supported by most professional backup suites today (including Backup Exec and ArcServe IT). You can have the software make a set of floppy discs, which will allow you to boot the crashed server. They will automatically address the streamer and start the recovery procedure after key pressed - the installed OS that has been damaged will be overwritten. This process is still lasting quite a while, but it is definitely much safer and faster than re-installing the whole operating system and software - which will certainly take days until everything will work again.