A new wrinkle to this comparison is the release of a 300 dpi version of the Oynx C67ML in 2016. I haven't found any English language sources about this "Carta2" version but the Chinese reviews on Taobao seem pretty positive.
I will probably go for the Boyue T62D anyway since it's available at a local store here in Taiwan for just 3000NTD (~90 USD). The new C67ML is available from a Taiwanese online reseller for about 170 USD, a significant mark-up over the ~130 USD price on Taobao.
Here's the link to a pretty comprehensive overview of the new C67ML from the Chinese Onyx site:
http://www.onyx-international.com/in...10-20-06-28-47