Got it in March 2019 and its still going, which it should be. Obviously I've not compared it to other 4k drives but I'm happy with it. Only done about 25 actual 4K discs, but its used for ordinary BR as well.
Did the firmware myself. Far as I remember it was, after stressing out about firmware, I'm going to brick it, I never update firmware unless I really have too etc, really easy and took about a minute.
Haven't looked at MakeMKV forums an awful lot about firmware since, but think there was something about there being later versions that made it more difficult to downgrade to previous (ripping) versions, but also think there was something about that being overcome again. So probably best to browse around a bit more about that, as I shall, now you've got me interested again...
Edit: the Marty person sending modified drives seems to have satisfied customers from looking through the threads. No personal experience of course. Course, not sure about postage at the moment.