On May 5, 2004, at 12:05 PM, Jukka Marin wrote:
> Looking for a larger backup media, I was offered a DLT drive and a HP
> DAT72 drive.  The DLT drives cost twice as much and the DLT tapes are
> 25% more expensive than DAT72 tapes.  I'm being told that DLT is more
> reliable.

I've been using DLT and now sDLT drives for about 5 years.  I've got
about three years of daily incrementals on DLT-III, about a year on 
DLT-IV,
and we switched to sDLT 220 two years ago.  Using Legato 
Networker/Solstice Backup on a Sun, although tar and dump work fine as 
well.

With regard to reliability: so far, so good.  I've had one or two tapes 
which failed the first time they were used with a write error, but the 
error was detected (not ignored), and I've not yet had a tape that was 
supposedly written OK fail when read.  I've restored large amounts of 
data from the tapes successfully, say ~200 GB read from two dozen tapes 
out of the ~90 that have been written to.  DLT cartidges are much 
sturdier than 4-mm DDS DAT tapes, and they
have a better tape transport mechanism.

-- 
-Chuck