Like anything else, you need to do your research, and yes, some folks are unlucky. Having a bad run, or a couple bad runs early on in the production of a particular product is not unusual, no matter where that product is made or what brand it is.
Anyone remember the boot-looping problem with LG phones a couple years ago? I'm on my third LG phone and never had that problem, yet a fair number of people were unlucky and experienced the issue.
One of the reasons I waited to try a Topping DAC was due to the reliability issues with certain models. I was also very skeptical of Chinese brands in general. What I did was buy a small SMSL DAC for ~$100 that I use at my desk. I've had it for over a year with no problems. That gave me more confidence in these brands like Topping, SMSL, et. al.
Fingers crossed on my new DX3Pro. If it develops problems, I will likely try a different Topping or SMSL model.