question

You shouldn't use billboard objects at all when designing a model for VR.

In general, you should avoid requiring the user’s eyes to make rapid and frequent adjustments in distance, such as switching focus between a distant object and nearby HUD element. Instead, consider having your interface elements as intuitive and immersive parts of the 3D world. See Oculus Rift Best Practices Guide for VR Development and Minimum Age (roadtovr.com)

If you really want something drawn in front of the user's face, position it relative to the headset in 3D space rather than trying to stick it onto the screen:

if (stick(-1, STICK_VR_STATUS)) {
       Array billboardRot = stick(-1, STICK_VR_HAND_WORLD_ROTATION);
       Array billboardPos = stick(-1, STICK_VR_HAND_OFFSET_POSITION, 0, [0,0,-2]);
       setcenter(BillboardObject, billboardPos[1], billboardPos[2], billboardPos[3]);
       setrot(BillboardObject, 90 + billboardRot[1], billboardRot[2], billboardRot[3]);
}

The FPS counter is useful for debugging your framerate during model development, but you should turn it off when actually experiencing the VR model. Because it is simply a debugging tool, it isn't particularly important how it is displayed, only that it can be seen during development.