I just spent two weeks working from Tensing Pen. The internet was very good - more than adequate for video conferences and data heavy web apps. However lightning damaged the wifi extender near the south end of the property and I sometimes had to relocate from my room (Pine Pillar) to the bar. They probably fixed the wifi by now but the bar there is a fantastic office - overhead fan kept me cool. I'd be happy to spend a month working from there.
Now I'm working from Treasure Beach where my guesthouse's wifi is strong but the internet is not so good (Flow).