Well, the only Thunderbolt 2 to HDMI adapter I've used that actually worked well (and I tried 2 others .. they're expensive too, I must have spent ~$150 in the

Well, the only Thunderbolt 2 to HDMI adapter I've used that actually worked well (and I tried 2 others .. they're expensive too, I must have spent ~$150 in the process) was the Belkin ones. The others didn't, for whatever reason, work when both Thunderbolt 2 ports were in use and the internal display was also turned on (on my '14 MBP). Other dongles for example randomly lost one of the color channels, had noisy output, occasionally flickered black or didn't work when waking up from sleep.