I have both the Tascam DA-30 and the Panasonic 3700. I've used both of them and consider the sound of the Panasonic unit to be much better.
The Tascam unit was somehow just "constricted" somehow sonically. I would use the Panasonic unit for mastering, because tapes sounded better
and the controls were much more ergonomic, and then use the Tascam to clone the master DAT if needed. There was a model 3800 also,
and it had a more extensive remote control.