The defect you write about was a disadvantage of the firmware and it was possible to correct it. Such a failure does not cross out all the next products of the company. Each producer has something behind his ears. A good example for Seagate is the ST1000DM003 model, initially released as a 64MB cache model. As there was a moment on the market, the producer did not praise too much, he broke the series into two models - one from 32MB cache, the other from 64MB cache. Of course, not praising this too much, the designation of the model remained the same for both disks, only after P / N and reading the specifications could be found the difference.
Otherwise, WD sells the Green series at the moment as Blue (previously, the Blue series had 7200 RPM, now they can suddenly have 5400 RPM). It is also not an interesting play, although at least the models differ and the parameters are not hidden.
I met with many of the defective Seagate drives. I have also encountered many defective WD drives. Statistically, I buy "half and half", once WD, once Seagate, I send a disc with a complaint one time, once to another company, it's even hard to say whether it is more to one than another. In general, new disks in my opinion are definitely more emergency than older constructions.
Recently, I also give Toshibom P300 a chance, even though the previous series (dt01ac100) did not impress me with their failure. But considering that Seagate or WD managed to get damaged after removing it from the foil (first scan, first inclusion, damaged sectors), I might as well change the Toshiba version.