Got my index controllers today and they are good. It feels so much better than my vive wands which were abysmal, grabbing stuff feels more natural and it is hard to accidentally press the system button, the front trigger is fucking amazing in comparison but the thumbsticks are meh they don't feel as good as the touchpad and other buttons.
The knuckle foam is fucking amazing I wish I had that in my 8kx.
For games the finger tracking is adequate and better suited than leap motion since the tracking is far more robust and you have haptic feedback which is important, but I find it is not as good as leapmotion for making gestures.
Leapmotion was not perfect but it was more natural, I messed around with it on my vive in the past in altspaceVR and big screen.
I could use leap motion with my vive wands simultaneously despite the FoV and occlusion limitations you could clap and do all manner of gestures it came off more accurate and natural.
With the index controller when I open my hand and my fingers are far from the sensor there is a region where it is woefully inaccurate and just snaps into an open hand.

It didn't affect gameplay for me so far though the issue is mostly just aesthetic, bolt action was fun as hell in H3VR but it really needs a stock, gotta figure out how to make a simple rifle stock for it that you just grab when needed and throw aside when not required without the need for fixtures/magnets like the commercial peripherals I've seen.
I am thinking of just using a threaded rod and some 3D printed thin/hollow curved paddles that don't affect the finger/grasp tracking.
Only practical solution seems to be curved grips that follow the contour of the controller with the rod at the bottom.