I never ventured into digital tape formats, although I got into recordable a/v discs early on. I still have lots of tape gear, though I favor digital formats and LP's. Also embraced hard drives. my main system has three, and I own six total, nine inclucing PC's.
For awhile, we sold large quantities of DAT's to data shops when I was in the computer industry. At that time, there were data cartridges with far higher capacity, which we sold in mega quantities to large data shops. Optical media obsoleted all the computer tape formats. Sorry, if I'm now reminiscing about a whole 'nother business.
For photos & more info on Triad/That's cassettes: http://vintagecassettes.com/triad_thats/triad_thats.htm