Once you get to the location on the lower lefthand side of the map marked with a star, drop onto the ground and run towards the Insight. Before you make it to the Insight, you will a hole in the ground; jump in here and immediately start gliding. On the wall of this hole, you will see a platform with the final Mastery Insight.
Turning while tapping the drift key, vs turning while holding the drafting key, I notice that both methods the mount still wont really turn until the flames turn blue from red. It really helps for me, personally, to be zoomed out more when using the beetle so I can switch direction faster and bump into fewer obstacles.The whole point of any mount is that it doesn't render another mount useless. If the Roller Beetle's endurance bar would be full the moment you mount it, nobody would take out their Raptor anymore. Also, don't forget that the beetle accelerates when you go downhill, regardless of special mount skills.
by The Guild Wars 2 Team on June 28, 2018 Go behind the scenes with the Guild Wars 2 Mounts Team to learn all about designing the roller beetle, a new mount available in the latest Living World episode !
From Guild Wars 2 Wiki. Right-click to preview available mount skins. — In-game description. Tremor Armadillo Roller Beetle Skin (choice) 7c0Fn.