If you preferred the sound of your DAT recordings to "tapeless" recordings later on, I won't discount that impression, but it must have been because of something other than the recording medium.
As others have pointed out, DAT is just a neutral "bit bucket" that stores and replays PCM audio data. Today's silicon-based recorders cut out the mechanical transport and tape, which are fragile and subject to accidents and wear, but in principle the A/D and D/A stages around the recording process are the same as with DAT.
So like I said, maybe you liked the particular way that your particular mikes (in the places you put them back then, with the particular performances that you recorded) sounded when their signals went into your D8, more than you like the way they sound with any recorder that you may have used since then. But the DAT medium itself has no sonic character as such; it can't.
--Are blank DATs being made any more? The highly miniaturized, helical scan format requires almost incredible physical precision. I wouldn't trust any tape stock that had been sitting on a shelf (in unknown temperature and humidity) for 5+ years; even the tiniest amount of warping and weaving can interfere with tape-to-head contact.
BTW the D7 and D8, etc., used half-sized head drums, which are fine in a recorder--but when playing back a DAT, the tape-to-head contact is more reliable with a full-size head drum (less severe angles of tape wrap, and the two playback heads on opposite sides of the drum can sometimes read "iffy" data that a single head might not be able to read reliably). So the error / dropout rate is lower on decks that have full-size head drums--plus they're less vulnerable to the effects of head clogs and wear. If I were using DAT to record any more, I would use the recorder strictly as a recorder, and use a separate machine (again, with a full-sized drum) for playbacks and transfers.