Works well with Termux (especially with Emacs)?

Yea it works with Termux just fine. We're working on getting a better solution for programming though :)

Hmmm...I can access github from Beijing without any problems... (I am using Google's DNS servers)

Traffic directed at 8.8.8.8 and 8.8.4.4 is not always reliable (intercepted and malformed) where I life. I use mostly opendns and a tunneled dns proxy back to some servers i have. Bu yes, it works by avoiding the poisoned dns servers