They are used to cater for longhaul flights at HKT so I expect no issues. No first hand experience though.
The TK flight ex HKT is the very early morning departure right? - so I expect C pax to sleep anyway for the first part of the flight (I know I would party/go clubbing in Patong in the evening/night and then proceed to the airport at 3AM for the 05:50AM departure so I would have no issues sleeping for the first hours of the flight)