I think you dont need both (T16000 Stick and TWCS) for Arma3.
The T16000 Stick only has enough controller / knobs for ArmA.
Arma hasnt so much controllersettings for the Jets.
My Youtube FlightSim Channel is in german language (maybe it is useless for you) but there you will find more Information about Sticks/Controller and configuration of the hardware in Flight Sim Games.
https://www.youtube.com/user/lessing999
Arma3 ingame controller list:
i use all the controller for other flightsim Games.
All of them are working very well in Arma3 and the headtracking system in Arma3 has the smoothes movement of all of my flightsim games! (Rise of Flight, IL2 Sturmovik Battle of Stalingrad/Moscow/Kuban, DCS World, etc.) But you dont need so many controller for ArmA3!
Before you spend 50-70 Euro for the TWCS you better try to get a second hand headtracking system (i payed 40 Euros for my second hand headtrackingsystem (clip and moddified PS3 cam) and i use the opentrack freeware)
A headtracking system is one of the most important things for flightsim games.
For example (the clip without camera):
https://www.trackhat.org/single-post/2017/02/07/The-new-TrackHat-clip-head-tracker
complete system with clip and camera:
https://www.trackhat.org/product-page/trackhat-clip-head-tracking-kit
You see, it isnt so expansive but you will love it from the first time you start flying with headtracker.