Are all LTO2 drives as unreliable as I have been experiencing ?

We installed our first 3583 with 2-LTO2 drives, about a year ago. Of the
two drives, both have been replaced at least one. I just replace one of
the replacements, again (wouldn't power up). The first replacement was
after about a month of usage !

We just upgraded our configuration by adding 2-drives to the existing
library and purchasing another 3583 with 4-drives.  These have now been in
use for about 2-weeks.

Of the 2-new drives added to the old library, one of them is already
showing signs of problems (shows A! on the panel, which the book says
drive hardware fault).

Of my 9+ years of experience with 3590 (B and E) drives, I have never seen
so many failures. Especially considering the amount of tapes that have
been fed through the 3590 drives (the 4-E drives run through over
200-mounts a day).

Is this normal ?

Also, no I do not push what I consider a lot of data through these drives
(~ 1TB per week).

What kind of experiences do other folks have with IBM 3580 LTO2 drives,
when it comes to reliability ?